L&#39;attuale ricerca è finanziata dalla Fondazione Solorz-Zak Research.

Tutte le procedure chirurgiche sono stati sottoposti a esame etico e approvati dal governo dell&#39;Alta Baviera (numero di riferimento: 55.2-1-54-2532.3-13-13 e -2532-136-11). Animali sono maschio C57BL / 6 topi con un peso corporeo di circa 25 g. 1. Preparazione degli animali <ol><li> Indurre l&#39;anestesia mettendo il mouse in una camera. Lavare la camera con il 5% isoflurano fino a quando l&#39;animale perde conoscenza. </li><li> Iniettare anestetici premiscelati intraperitoneale: fentanil (0,05 mg / kg), midazolam (5 mg / kg) e medetomidina (0,5 mg / kg). Controllare i riflessi prima e regolarmente durante la procedura. Reinject terzo del quantitativo iniziale oraria per mantenere l&#39;anestesia. </li><li> Intubare orotracheally con un tubo da un catetere venoso 11 G 20. Per intubazione fissare l&#39;animale su una piattaforma inclinata (30 °), ritrarre la lingua con una pinza piegate, visualizzare le corde vocali sotto un microscopio funzionamento e inserire il tubo nella tracheadurante l&#39;inspirazione. </li><li> Posizionare il mouse in posizione prona e controllare il corretto posizionamento del tubo con un pezzo di cotone o un microcapnograph. </li><li> Collegare il tubo di intubazione al respiratore. Ventilare il mouse con aria ambiente supplementato con 25% di ossigeno con una frequenza di 180-220 respiri / min e un volume di pompaggio di 200-250 microlitri. </li><li> Collegare il tubo di intubazione al microcapnograph. Mantenere la fine espirazione pCO 2 a 30 mmHg regolando la frequenza di ventilazione. </li><li> Inserire una sonda di temperatura rettale e posizionare l&#39;animale su una piastra elettrica per mantenere 37 ° C la temperatura corporea. </li><li> Applicare il sensore pulsoximeter anulare sulla zampa posteriore destra. </li><li> Aprire la pelle sopra il cranio con un paio di forbici. L&#39;incisione dovrebbe essere lungo circa 0,5 cm di lunghezza e tra orecchio e occhio. </li><li> Sezionare il muscolo temporale sinistro con un bisturi dall&#39;osso temporale. </li><li> Incollare il misuratore laser Doppler (LDF) sondal&#39;osso temporale sinistro. Tenere la sonda in una posizione fissa che la colla si indurisce. </li><li> Praticare un foro di circa 1,5 mm di diametro con un trapano dentistico nell&#39;osso temporale sinistro. Raffreddare l&#39;osso con soluzione salina per evitare danni dovuti al calore. </li><li> Inserire la sonda ICP nella cavità cranica. Spingere in avanti come dorsale possibile per evitare danni ai tessuti cerebrali e sanguinamento. </li><li> Se la sonda si trova nella posizione giusta, correggere e sigillarlo con cemento. Lasciare il cemento secco per 5 min. </li><li> Girate con attenzione il mouse in una posizione supina. </li><li> Per il monitoraggio continuo della pressione arteriosa, cateterizzare l&#39;arteria femorale di sinistra. </li><li> Collegare il catetere femorale al dispositivo di monitoraggio della pressione sanguigna. </li></ol> 2. SAH induzione <ol><li> Aprire la pelle con un paio di forbici da sterno al mento (2 cm). Sezionare il tessuto connettivo senza mezzi termini e spingere le ghiandole salivari parte. </li><li> Esporre l&#39;arteria carotide comune sinistra (CCA) e mobilitare esso. Preservare l&#39;nervo vago, che corre nella stessa guaina di tessuto connettivo come la CCA. Spostare cranica ed esporre e mobilitare l&#39;ICA e la Corte dei conti utilizzando la stessa tecnica. </li><li> Legare la Corte dei conti, per quanto craniale possibile. </li><li> Predisporre altri due legature per il filamento attorno alla Corte dei conti. </li><li> Occludere il CCA e ICA temporaneamente microclips. Posizionare i microclips con un applicatore microclip. Assicurarsi che i clip vengono applicate correttamente tirandoli delicatamente indietro. </li><li> Tagliare un foro per l&#39;inserimento filamento nella ECA con una forbice nave. </li><li> Inserire un filamento Prolene 5-0 con 12 mm di lunghezza nella ECA. </li><li> Chiudere il sito di inserimento con una sola legatura predisposto. </li><li> Rimuovere i microclips con un applicatore microclip dal CCA e ICA. </li><li> Far avanzare il filo con una pinza nella ICA fino alla ICP aumenta. Un improvviso aumento della ICP indica induzione sanguinamento. </li><li> Ritirare immediatamente il filamento e legare la Corte dei conti chiudendo entrambi prlegature earranged consecutivamente. Questo impedisce sanguinamento dal sito di inserzione. </li><li> Suturare la ferita della pelle. </li><li> Monitorare i parametri fisiologici dell&#39;animale per altri 20 min. </li><li> Rimuovere ICP e le sonde LDF e suturare la ferita della pelle. </li></ol> 3. End of Experiment <ol><li> Perfusione l&#39;animale transcardially con 20 ml di soluzione fisiologica (temperatura ambiente) seguiti da 20 ml di PFA 4% in PBS (4 ° C). </li><li> Sezionare il cervello dal cranio. Tagliare il cranio sulla linea mediana e tra le cavità orbitali. Quindi rimuovere l&#39;osso dal cervello. </li><li> Valutare la distribuzione sangue nello spazio subaracnoideo. </li></ol> 4. Considerazioni in caso di vita Surgery (non mostrato nel video) <ol><li> Iniettare Carprofen (4 mg / kg per via sottocutanea) per l&#39;analgesia postoperatoria direttamente dopo l&#39;induzione dell&#39;anestesia. Durante il periodo di osservazione postoperatoria Carprofen (4 mg / kg per via sottocutanea) viene iniettato ogni 24 ore. </li&gt; <li> Invece di misurazione della pressione arteriosa invasiva fare uso di un sistema di monitoraggio della pressione arteriosa non invasiva. </li><li> Per la terminazione di anestesia iniezione sottocutanea agenti antagonizzare: naloxone (1.2 mg / kg), flumazenil (0,5 mg / kg) e atipamezolo (2,5 mg / kg). </li><li> Estubare l&#39;animale. </li><li> Dopo aver ripreso dei riflessi mettere l&#39;animale in una camera preriscaldato. Mantenere l&#39;animale a circa 32 ° C per 24 ore. </li><li> Gli animali vengono controllati per respirazione spontanea e la loro condizione generale durante le prime ore dopo l&#39;intervento. Se il tronco cerebrale è influenzata animali hanno problemi di respirazione e devono essere eutanasia. </li><li> Gli animali vengono verificati ogni giorno per la loro condizione generale e del peso corporeo e per neurologiche e sensoriali deficit 15. </li></ol>

<ol>
	<li>Cahill, J., Zhang, J. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Subarachnoid+hemorrhage:+is+it+time+for+a+new+direction.">Subarachnoid hemorrhage: is it time for a new direction.</a> Stroke. 40, 86-87 (2009).</li><li>van Gijn, J., Kerr, R. S., Rinkel, G. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Subarachnoid+haemorrhage.">Subarachnoid haemorrhage.</a> Lancet. 369, 306-318 (2007).</li><li>Lin, C. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+murine+model+of+subarachnoid+hemorrhage-induced+cerebral+vasospasm.">A murine model of subarachnoid hemorrhage-induced cerebral vasospasm.</a> J. Neurosci. Methods. 123, 89-97 (2003).</li><li>Altay, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+method+for+subarachnoid+hemorrhage+to+induce+vasospasm+in+mice.">A novel method for subarachnoid hemorrhage to induce vasospasm in mice.</a> J. Neurosci. Methods. 183, 136-140 (2009).</li><li>Feiler, S., Friedrich, B., Scholler, K., Thal, S. C., Plesnila, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Standardized+induction+of+subarachnoid+hemorrhage+in+mice+by+intracranial+pressure+monitoring.">Standardized induction of subarachnoid hemorrhage in mice by intracranial pressure monitoring.</a> J. Neurosci. Methods. 190, 164-170 (2010).</li><li>Bederson, J. B., Germano, I. M., Guarino, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cortical+blood+flow+and+cerebral+perfusion+pressure+in+a+new+noncraniotomy+model+of+subarachnoid+hemorrhage+in+the+rat.">Cortical blood flow and cerebral perfusion pressure in a new noncraniotomy model of subarachnoid hemorrhage in the rat.</a> Stroke. 26, 1086-1091 (1995).</li><li>Veelken, J. A., Laing, R. J., Jakubowski, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+Sheffield+model+of+subarachnoid+hemorrhage+in+rats.">The Sheffield model of subarachnoid hemorrhage in rats.</a> Stroke. 26, 1279-1283 (1995).</li><li>Kamii, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Amelioration+of+vasospasm+after+subarachnoid+hemorrhage+in+transgenic+mice+overexpressing+CuZn-superoxide+dismutase.">Amelioration of vasospasm after subarachnoid hemorrhage in transgenic mice overexpressing CuZn-superoxide dismutase.</a> Stroke. 30, 867-871 (1999).</li><li>Parra, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mouse+model+of+subarachnoid+hemorrhage+associated+cerebral+vasospasm:+methodological+analysis.">Mouse model of subarachnoid hemorrhage associated cerebral vasospasm: methodological analysis.</a> Neurol. Res. 24, 510-516 (2002).</li><li>Broderick, J. P., Brott, T. G., Duldner, J. E., Tomsick, T., Leach, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Initial+and+recurrent+bleeding+are+the+major+causes+of+death+following+subarachnoid+hemorrhage.">Initial and recurrent bleeding are the major causes of death following subarachnoid hemorrhage.</a> Stroke. 25, 1342-1347 (1994).</li><li>Thal, S. C., Plesnila, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Non-invasive+intraoperative+monitoring+of+blood+pressure+and+arterial+pCO2+during+surgical+anesthesia+in+mice.">Non-invasive intraoperative monitoring of blood pressure and arterial pCO2 during surgical anesthesia in mice.</a> J. Neurosci. Methods. 159, 261-267 (2007).</li><li>Hockel, K., Trabold, R., Scholler, K., Torok, E., Plesnila, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+of+anesthesia+on+pathophysiology+and+mortality+following+subarachnoid+hemorrhage+in+rats.">Impact of anesthesia on pathophysiology and mortality following subarachnoid hemorrhage in rats.</a> Exp. Transl. Stroke Med. 4, 5 (2012).</li><li>Wang, Z., Schuler, B., Vogel, O., Arras, M., Vogel, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=What+is+the+optimal+anesthetic+protocol+for+measurements+of+cerebral+autoregulation+in+spontaneously+breathing+mice?.">What is the optimal anesthetic protocol for measurements of cerebral autoregulation in spontaneously breathing mice?.</a> Exp. Brain Res. 207, 249-258 (2010).</li><li>Schwartz, A. Y., Masago, A., Sehba, F. A., Bederson, J. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+models+of+subarachnoid+hemorrhage+in+the+rat:+a+refinement+of+the+endovascular+filament+model.">Experimental models of subarachnoid hemorrhage in the rat: a refinement of the endovascular filament model.</a> J. Neurosci. Methods. 96, 161-167 (2000).</li><li>Feiler, S., Plesnila, N., Thal, S. C., Zausinger, S., Scholler, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Contribution+of+matrix+metalloproteinase-9+to+cerebral+edema+and+functional+outcome+following+experimental+subarachnoid+hemorrhage.">Contribution of matrix metalloproteinase-9 to cerebral edema and functional outcome following experimental subarachnoid hemorrhage.</a> Cerebrovasc. Dis. 32, 289-295 (2011).</li></ol>

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Le opzioni di trattamento dopo SAH sono scarse e per lo più inefficace. Pertanto la fisiopatologia del danno cerebrale post-emorragica deve essere ulteriormente compreso per identificare nuovi bersagli terapeutici e sviluppare nuovi approcci terapeutici. Standardizzati e modelli animali ben riproducibili negli animali geneticamente modificati, ossia topi, sono cruciali per tali indagini. Il modello CWP è diventato un modello ampiamente utilizzato per SAH come assomiglia alla fisiopatologia nell&#39;uomo vicin...

SAH è il sottotipo corsa con il risultato meno favorevole per i pazienti: 40% dei pazienti muoiono entro un mese dopo l&#39;emorragia 1 e sopravvissuti raramente avere un esito clinico favorevole. La grande maggioranza di Sahs spontanei (80%) sono causati dalla rottura di aneurismi intracranici che in genere si trovano lungo la anteriore e comunicante posteriore, l&#39;arteria basilare e dell&#39;arteria cerebrale media (MCA) 2. Tali aneurismi sono difficili da modellare negli animali e quindi modelli animali di SAH sono o eseguite da iniezione di sangue nello spazio / ventricoli cerebrali subaracnoidea o da perforazione endovascolare di una nave subaracnoideo. Iniezione di sangue autologo nella cisterna magna è facile da eseguire e riproducibile come il volume di sangue può essere controllato direttamente 3. Purtroppo alcuni aspetti della fisiopatologia SAH, ad esempio illesione del vaso, non può essere modellato mediante questa procedura. Un altro approccio tecnico per l&#39;induzione di SAH è l&#39;apertura di una vena intracisternale 4. Tuttavia, il intraluminale CWP al ramo MCA sembra essere la procedura che modella l&#39;fisiopatologia nell&#39;uomo più strettamente 5. Il metodo è stato sviluppato e descritto nel ratto da Bederson e colleghi e allo stesso tempo da Veelken e colleghi 6,7. In seguito il modello di perforazione intraluminale è stato adattato ai topi 8,9. Un filamento è inserita nella carotide esterna (ECA) e avanzato alla base cranica attraverso l&#39;arteria carotide interna (ICA). Nel punto di diramazione del MCA filamento perfora la nave e induce un sanguinamento nello spazio subaracnoideo alla base del cranio. Il sangue distribuisce poi nello spazio subaracnoideo rimanente lungo fessure e vasi sanguigni. Bleeding è bloccata da formazione di coaguli nel sito di perforazione, ma rebleedings, which sono spesso deleteria nei pazienti 10, possono verificarsi. Di conseguenza, il modello filamento endovascolare diventato un modello SAH ampiamente utilizzato negli ultimi anni. Lo svantaggio più frequentemente citato del modello filamento perforazione è che il volume emorragia non può essere controllato direttamente e può quindi essere variabile. Questa variabilità può essere ridotto significativamente stretto controllo della fisiologia animale e post-emorragica ICP. I topi hanno il grande vantaggio che un gran numero di ceppi geneticamente modificati sono disponibili. Tuttavia, a causa delle loro dimensioni ridotte procedure chirurgiche tendono ad essere più complessa in specie più grandi, ad esempio topi o conigli. Pertanto, il downscaling di tecniche sviluppate per i ratti di topi spesso non porta ai risultati desiderati, ad esempio come topi hanno un peso corporeo e il volume sanguigno molto limitate tecniche non invasive per la pressione del sangue e analisi dei gas del sangue, nonché per la saturazione dell&#39;emoglobina e il monitoraggio della frequenza cardiacadevono essere applicate quando possibile. Di conseguenza, l&#39;obiettivo della pubblicazione corrente è di descrivere il modello perforazione filamento per SAH nei topi e per dimostrare come questo modello può essere eseguito in modo standardizzato ed altamente riproducibile.

<table border="1">
	<tbody>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Equipment</td>
		</tr>
		<tr>
			<td>operation microscope</td>
			<td>Leica</td>
			<td>KL2500</td>
			<td></td>
		</tr>
		<tr>
			<td>isoflurane vaporizer</td>
			<td>Harvard Instruments</td>
			<td>Continuous Flow Vaporizer</td>
			<td></td>
		</tr>
		<tr>
			<td>respirator</td>
			<td>Hugo Sachs</td>
			<td>Minivent 845</td>
			<td></td>
		</tr>
		<tr>
			<td>microcapnograph</td>
			<td>Hugo Sachs</td>
			<td>Type 340</td>
			<td></td>
		</tr>
		<tr>
			<td>temperature controller</td>
			<td>FHC</td>
			<td>DC Temperature Controller</td>
			<td></td>
		</tr>
		<tr>
			<td>dental drill</td>
			<td>Paggen</td>
			<td>Labset- N</td>
			<td></td>
		</tr>
		<tr>
			<td>ICP monitor</td>
			<td>Codman</td>
			<td>ICP monitor</td>
			<td></td>
		</tr>
		<tr>
			<td>blood pressure monitor</td>
			<td>AD Instruments</td>
			<td>Bridge Amp FE221</td>
			<td></td>
		</tr>
		<tr>
			<td>syringe pump</td>
			<td>World Precision Instruments</td>
			<td>SP101IZ</td>
			<td></td>
		</tr>
		<tr>
			<td>pulsoximeter</td>
			<td>Kent Scientific</td>
			<td>MouseSTAT</td>
			<td></td>
		</tr>
		<tr>
			<td>LDF</td>
			<td>Perimed</td>
			<td>Periflux 5000</td>
			<td></td>
		</tr>
		<tr>
			<td>analog data monitor</td>
			<td>AD Instruments</td>
			<td>Power Lab 16/35</td>
			<td></td>
		</tr>
		<tr>
			<td></td>
			<td></td>
			<td></td>
			<td>Material</td>
		</tr>
		<tr>
			<td>cement for ICP probe fixation</td>
			<td>Speiko</td>
			<td>Carboxylate cement</td>
			<td></td>
		</tr>
		<tr>
			<td>glue for LDF probe fixation</td>
			<td>Bob Smith Industries</td>
			<td>Cyanoacrylate glue (Maxi Cure and Insta Set)</td>
			<td></td>
		</tr>
		<tr>
			<td>venous catheter</td>
			<td>Johnson &#38; Johnson</td>
			<td>Jelco winged i.v. catheter; REF 4076</td>
			<td>modified intubation tube</td>
		</tr>
		<tr>
			<td>tubing for femoral catheter</td>
			<td>Smiths Medical</td>
			<td>Fine Bore Polythene Tubing; ID 0.28 mm OD 0.61 mm; REF 800/100/100</td>
			<td>cut to 30 cm length</td>
		</tr>
		<tr>
			<td>filament for vessel perforation</td>
			<td>Ethicon</td>
			<td>Prolene 5-0</td>
			<td>cut to 12 mm length</td>
		</tr>
		<tr>
			<td>surgical equipment</td>
			<td>Fine Scientific Instruments</td>
			<td>forceps medical #5, vessel scissors 8 cm, microclip 4 mm jaw</td>
			<td></td>
		</tr>
	</tbody>
</table>

a murine model of subarachnoid hemorrhage

In questa pubblicazione il video viene presentato un modello standardizzato di topo di emorragia subaracnoidea (SAH). Bleeding è indotta da Circolo endovascolare di Willis perforazione (CWP) e provato dalla pressione intracranica (ICP) di monitoraggio. In tal modo una distribuzione omogenea di sangue negli spazi subaracnoidei che circondano la circolazione arteriosa e fessure cerebellari è raggiunto. Fisiologia degli animali è gestito da intubazione, ventilazione meccanica, e continuo monitoraggio on-line di vari parametri fisiologici e cardiovascolari: la temperatura corporea, la pressione arteriosa sistemica, frequenza cardiaca e saturazione dell&#39;emoglobina. In tal modo la pressione di perfusione cerebrale può essere strettamente monitorati generando un volume meno variabile di sangue travasato. Questo permette una migliore standardizzazione delle endovascolare perforazione filamento nei topi e rende l&#39;intero modello altamente riproducibile. Così è prontamente disponibile per gli studi farmacologici e fisiopatologici in wild type e geneticaly alterato topi.

Mortalità Una volta che la tecnica chirurgica è padroneggiata la procedura non suscitare alcuna mortalità intraoperatoria. Sanguinamento può anche essere raggiunto in quasi tutti gli animali. La mortalità postoperatoria è del 30-40% con la maggior parte degli animali muore il giorno 1 dopo l&#39;intervento chirurgico (Figura 5). ICP valori dopo SAH L&#39;ICP prima del dissanguamento è di circa 4 mmHg. Sanguinamento r...

Watch this Scientific Journal Video about A Murine Model of Subarachnoid Hemorrhage at JoVE.com

A Murine Model of Subarachnoid Hemorrhage

Un modello di topo standardizzato di emorragia subaracnoidea da Circolo endoluminale di Willis perforazione viene descritto. Nave di perforazione e emorragia subaracnoidea sono monitorati da un monitoraggio della pressione intracranica. Inoltre diversi parametri vitali vengono registrati e controllati per mantenere condizioni fisiologiche.

Un modello murino di emorragia subaracnoidea

In this video publication a standardized mouse model of subarachnoid  hemorrhage (SAH) is presented. Bleeding is induced by endovascular Circle of  Willis ...

a-murine-model-of-subarachnoid-hemorrhage

Research

JoVE Journal

Medicine

19.5K Views.  University of Munich Medical Center.  Un modello di topo standardizzato di emorragia subaracnoidea da Circolo endoluminale di Willis perforazione viene descritto. Nave di perforazione e emorragia subaracnoidea sono monitorati da un monitoraggio della pressione intracranica. Inoltre diversi parametri vitali vengono registrati e controllati per mantenere condizioni fisiologiche. 

Video: A Murine Model of Subarachnoid Hemorrhage

A Low Mortality Rat Model to Assess Delayed Cerebral Vasospasm After Experimental Subarachnoid Hemorrhage

Objective: To characterize and establish a reproducible model that demonstrates delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) in rats, in order to identify the initiating events, pathophysiological changes and potential targets for treatment.
Methods: Twenty-eight male Sprague-Dawley rats (250 - 300 g) were arbitrarily assigned to one of two groups - SAH or saline control. Rat subarachnoid hemorrhage in the SAH group (n=15) was induced by double injection of autologous blood, 48 hr apart, into the cisterna magna. Similarly, normal saline (n=13) was injected into the cisterna magna of the saline control group. Rats were sacrificed on day five after the second blood injection and the brains were preserved for histological analysis. The degree of vasospasm was measured using sections of the basilar artery, by measuring the internal luminal cross sectional area using NIH Image-J software. The significance was tested using Tukey/Kramer's statistical analysis.
Results: After analysis of histological sections, basilar artery luminal cross sectional area were smaller in the SAH than in the saline group, consistent with cerebral vasospasm in the former group. In the SAH group, basilar artery internal area (.056 &mu;m &plusmn; 3) were significantly smaller from vasospasm five days after the second blood injection (seven days after the initial blood injection), compared to the saline control group with internal area (.069 &plusmn; 3; p=0.004). There were no mortalities from cerebral vasospasm.
Conclusion: The rat double SAH model induces a mild, survivable, basilar artery vasospasm that can be used to study the pathophysiological mechanisms of cerebral vasospasm in a small animal model. A low and acceptable mortality rate is a significant criterion to be satisfied for an ideal SAH animal model so that the mechanisms of vasospasm can be elucidated 7, 8. Further modifications of the model can be made to adjust for increased severity of vasospasm and neurological exams.

Aneurysmal subarachnoid hemorrhage (SAH) is bleeding that occurs into the subarachnoid space when an aneurysm ruptures. While the morbidity and mortality from this event has been on a decline due to improved treatment approaches, the risk of vasospasm after subarachnoid hemorrhage continues to be the same as it was several years ago. The importance of establishing a comprehensive and reproducible animal model to identify initiating events of cerebral vasospasm has been the focus of research since the first use of rats in an experimental vasospasm model in 1979 by Barry et al. Early work in rats demonstrated that a single injection of autologous blood into the cisterna magna led to acute (within minutes) but not delayed cerebral vasospasm 3, 6, 14. Here we characterize a low mortality SAH rat model that results in reproducible delayed vasospasm.

Un basso Rat modello di mortalità per valutare ritardata vasospasmo cerebrale dopo emorragia subaracnoidea sperimentale

Objective: To characterize and establish a reproducible model that demonstrates delayed cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) ...

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Medicina

Murine Model of Wound Healing

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. Impaired wound healing, which occurs in diabetic patients for example, can lead to severe unfavorable outcomes such as amputation. There is, therefore, an increasing impetus to develop novel agents that promote wound repair. The testing of these has been limited to large animal models such as swine, which are often impractical. Mice represent the ideal preclinical model, as they are economical and amenable to genetic manipulation, which allows for mechanistic investigation. However, wound healing in a mouse is fundamentally different to that of humans as it primarily occurs via contraction. Our murine model overcomes this by incorporating a splint around the wound. By splinting the wound, the repair process is then dependent on epithelialization, cellular proliferation and angiogenesis, which closely mirror the biological processes of human wound healing. Whilst requiring consistency and care, this murine model does not involve complicated surgical techniques and allows for the robust testing of promising agents that may, for example, promote angiogenesis or inhibit inflammation. Furthermore, each mouse acts as its own control as two wounds are prepared, enabling the application of both the test compound and the vehicle control on the same animal. In conclusion, we demonstrate a practical, easy-to-learn, and robust model of wound healing, which is comparable to that of humans.

A murine model of cutaneous wound healing that can be used to assess therapeutic compounds in physiological and pathophysiological settings.

Modello murino di guarigione delle ferite

Wound healing and repair are the most complex biological processes that occur in human life. After injury, multiple biological pathways become activated. ...

A New Murine Model of Endovascular Aortic Aneurysm Repair

Endovascular aneurysm exclusion is a validated technique to prevent aneurysm rupture. Long-term results highlight technique limitations and new aspects of Abdominal aortic aneurysm (AAA) pathophysiology. There is no abdominal aortic aneurysm endograft exclusion model cheap and reproducible, which would allow deep investigations of AAA before and after treatment. We hereby describe how to induce, and then to exclude with a covered coronary stentgraft an abdominal aortic aneurysm in a rat. The well known elastase induced AAA model was first reported in 19901 in a rat, then described in mice2. Elastin degradation leads to dilation of the aorta with inflammatory infiltration of the abdominal wall and intra luminal thrombus, matching with human AAA. Endovascular exclusion with small covered stentgraft is then performed, excluding any interactions between circulating blood and the aneurysm thrombus. Appropriate exclusion and stentgraft patency is confirmed before euthanasia by an angiography thought the left carotid artery. Partial control of elastase diffusion makes aneurysm shape different for each animal. It is difficult to create an aneurysm, which will allow an appropriate length of aorta below the aneurysm for an easy stentgraft introduction, and with adequate proximal and distal neck to prevent endoleaks. Lots of failure can result to stentgraft introduction which sometimes lead to aorta tear with pain and troubles to stitch it, and endothelial damage with post op aorta thrombosis. Giving aspirin to rats before stentgraft implantation decreases failure rate without major hemorrhage. Clamping time activates neutrophils, endothelium and platelets, and may interfere with biological analysis.

Histological and biochemical modifications after aneurysm endograft exclusion are still unclear. We describe a new model of endograft implantation on a murine aneurysm. Through thrombus analysis with and without persistant circulating blood stream interface, and new endovascular biomaterials evaluation, this model will help to better understand endovascular aneurysm exclusion pathobiology.

Un nuovo modello murino di endovascolare aneurisma dell&#39;aorta riparazione

Endovascular aneurysm exclusion is a validated technique to prevent aneurysm rupture. Long-term results highlight technique limitations and new aspects of ...

Intrastriatal Injection of Autologous Blood or Clostridial Collagenase as Murine Models of Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a common form of cerebrovascular disease and is associated with significant morbidity and mortality. Lack of effective treatment and failure of large clinical trials aimed at hemostasis and clot removal demonstrate the need for further mechanism-driven investigation of ICH. This research may be performed through the framework provided by preclinical models. Two murine models in popular use include intrastriatal (basal ganglia) injection of either autologous whole blood or clostridial collagenase. Since, each model represents distinctly different pathophysiological features related to ICH, use of a particular model may be selected based on what aspect of the disease is to be studied. For example, autologous blood injection most accurately represents the brain&#39;s response to the presence of intraparenchymal blood, and may most closely replicate lobar hemorrhage. Clostridial collagenase injection most accurately represents the small vessel rupture and hematoma evolution characteristic of deep hemorrhages. Thus, each model results in different hematoma formation, neuroinflammatory response, cerebral edema development, and neurobehavioral outcomes. Robustness of a purported therapeutic intervention can be best assessed using both models. In this protocol, induction of ICH using both models, immediate post-operative demonstration of injury, and early post-operative care techniques are demonstrated. Both models result in reproducible injuries, hematoma volumes, and neurobehavioral deficits. Because of the heterogeneity of human ICH, multiple preclinical models are needed to thoroughly explore pathophysiologic mechanisms and test potential therapeutic strategies.

Preclinical models of intracerebral hemorrhage are utilized to mimic certain aspects of clinical disease. Thus, mechanisms of injury and potential therapeutic strategies may be explored. In this protocol, two models of intracerebral hemorrhage are described, intrastriatal (basal ganglia) injections of autologous blood or collagenase.

Iniezione intrastriatali di sangue autologo o Clostridial Collagenase come modelli murini di emorragia intracerebrale

Intracerebral hemorrhage (ICH) is a common form of cerebrovascular disease and is associated with significant morbidity and mortality. Lack of effective ...

A Preclinical Murine Model of Hepatic Metastases

Numerous murine models have been developed to study human cancers and advance the understanding of cancer treatment and development. Here, a preclinical, murine pancreatic tumor model of hepatic metastases via a hemispleen injection of syngeneic murine pancreatic tumor cells is described. This model mimics many of the clinical conditions in patients with metastatic disease to the liver. Mice consistently develop metastases in the liver allowing for investigation of the metastatic process, experimental therapy testing, and tumor immunology research.

A preclinical, murine model of hepatic metastases performed via a hemispleen injection technique.

Un preclinici Modello murino di metastasi epatiche

Numerous murine models have been developed to study human cancers and advance the understanding of cancer treatment and development. Here, a preclinical, ...

The Rabbit Blood-shunt Model for the Study of Acute and Late Sequelae of Subarachnoid Hemorrhage: Technical Aspects

Early brain injury and delayed cerebral vasospasm both contribute to unfavorable outcomes after subarachnoid hemorrhage (SAH). Reproducible and controllable animal models that simulate both conditions are presently uncommon. Therefore, new models are needed in order to mimic human pathophysiological conditions resulting from SAH.
This report describes the technical nuances of a rabbit blood-shunt SAH model that enables control of intracerebral pressure (ICP). An extracorporeal shunt is placed between the arterial system and the subarachnoid space, which enables examiner-independent SAH in a closed cranium. Step-by-step procedural instructions and necessary equipment are described, as well as technical considerations to produce the model with minimal mortality and morbidity. Important details required for successful surgical creation of this robust, simple and consistent ICP-controlled SAH rabbit model are described.

The experimental intracranial pressure-controlled blood shunt subarachnoid hemorrhage (SAH) model in the rabbit combines the standard procedures &#8212; subclavian artery cannulation and transcutaneous cisterna magna puncture, which enables close mimicking of human pathophysiological conditions after SAH. We present step-by-step instructions and discuss key surgical points for successful experimental SAH creation.

Il Coniglio Blood-shunt modello per lo studio di acuta e sequele tardive di emorragia subaracnoidea: Aspetti tecnici

Early brain injury and delayed cerebral vasospasm both contribute to unfavorable outcomes after subarachnoid hemorrhage (SAH). Reproducible and ...

A Murine Model of Irreversible and Reversible Unilateral Ureteric Obstruction

Obstruction of the kidney may affect native or transplanted kidneys and results in kidney injury and scarring. Presented here is a model of obstructive nephropathy induced by unilateral ureteric obstruction (UUO), which can either be irreversible (UUO) or reversible (R-UUO). In the irreversible UUO model, the ureter may be obstructed for variable periods of time in order to induce increasingly severe renal inflammation and interstitial fibrotic scarring. In the reversible R-UUO model the ureter is obstructed to induce hydronephrosis, tubular dilation and inflammation. After a suitable period of time the ureteric obstruction is then surgically reversed by anastomosis of the severed previously obstructed ureter to the bladder in order to allow complete decompression of the kidney and restoration of urinary flow to the bladder. The irreversible UUO model has been used to investigate various aspects of renal inflammation and scarring including the pathogenesis of disease and the testing of potential anti-inflammatory or anti-fibrotic therapies. The more challenging model of R-UUO has been used by some investigators and does offer significant research potential as it allows the study of inflammatory and immune processes and tissue remodeling in an injured and scarred kidney following the removal of the injurious stimulus. As a result, the R-UUO model offers investigators the opportunity to explore the resolution of kidney inflammation together with key aspects of tissue repair. These experimental models are of relevance to human disease as patients often present with obstruction of the renal tract that requires decompression and are commonly left with significant residual kidney impairment that has no current treatment options and may lead to eventual end stage kidney failure.

The murine model of irreversible unilateral ureteric obstruction (UUO) is presented together with the model of reversible UUO in which the ureteric obstruction is relieved by anastomosis of the severed ureter into the bladder. These models enable the study of renal inflammation and scarring as well as tissue remodeling.

Un modello murino di irreversibile e reversibile unilaterale Ureteric Ostruzione

Obstruction of the kidney may affect native or transplanted kidneys and results in kidney injury and scarring. Presented here is a model of obstructive ...

Integrated Compensatory Responses in a Human Model of Hemorrhage

Hemorrhage is the leading cause of trauma-related deaths, partly because early diagnosis of the severity of blood loss is difficult. Assessment of hemorrhaging patients is difficult because current clinical tools provide measures of vital signs that remain stable during the early stages of bleeding due to compensatory mechanisms. Consequently, there is a need to understand and measure the total integration of mechanisms that compensate for reduced circulating blood volume and how they change during ongoing progressive hemorrhage. The body&#39;s reserve to compensate for reduced circulating blood volume is called the &#39;compensatory reserve&#39;. The compensatory reserve can be accurately evaluated with real-time measurements of changes in the features of the arterial waveform measured with the use of a high-powered computer. Lower Body Negative Pressure (LBNP) has been shown to simulate many of the physiological responses in humans associated with hemorrhage, and is used to study the compensatory response to hemorrhage. The purpose of this study is to demonstrate how compensatory reserve is assessed during progressive reductions in central blood volume with LBNP as a simulation of hemorrhage.

The purpose of this protocol is to demonstrate the techniques for measuring compensatory responses to reduced central blood volume using lower body negative pressure as a noninvasive experimental model of human hemorrhage which can be used to quantify the total integration of compensatory mechanisms to blood volume deficit in humans.

Le risposte compensative integrati in un modello umano di emorragia

Hemorrhage is the leading cause of trauma-related deaths, partly because early diagnosis of the severity of blood loss is difficult. Assessment of ...

Isometric Contractility Measurement of the Mouse Mesenteric Artery Using Wire Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and drugs. It is widely used in many studies on the physiological functions of vascular smooth muscle, the pathogenesis of vascular diseases such as hypertension, and the development of smooth muscle relaxant drugs. The mouse is a widely used model animal with a large pool of disease models and genetically modified strains. We introduced this method to measure the isometric contraction of mouse mesenteric artery in detail. A 1.4-mm segment of mouse mesenteric resistance artery was isolated and mounted on a myograph chamber by passing two steel wires through its lumen. After equilibration and normalization steps, the vessel segment was potentiated by a high-K+ solution twice prior to the contraction assay. As an example of the application of this method in drug development, we measured the relaxant effect of a novel natural substance, neoliensinine, isolated from a Chinese herb, embryos of the lotus seed (Nelumbo nucifera Gaertn.) on mouse mesenteric arteries. The vessel segments mounted on the myograph chamber were stimulated with a high-K+ solution. When the force tension reached a stable sustained phase, cumulative doses of neoliensinine were added to the chamber. We found that neoliensinine had a dose-dependent relaxant effect on smooth muscle contraction, thus suggesting that it bears potential activity against hypertension. In addition, as the vessel segment can survive at least 4 hours after mounting and maintain contractility induced by the high-K+ solution for many times, we suggest that the wire myograph system may be used for the time-consuming process of drug screening.

The wire myograph technique is used to investigate vascular smooth muscle functions and screen new drugs. We report a detailed protocol for measuring the isometric contractility of the mouse mesenteric artery and for screening new relaxants of vascular smooth muscle.

Misurazione di contrattilità isometrica dell'arteria mesenterica Mouse con filo Myography

The wire myograph technique is used to assess the contractility of vascular smooth muscles in response to depolarization, GPCR agonists/inhibitors and ...

A Preclinical Controlled Cortical Impact Model for Traumatic Hemorrhage Contusion and Neuroinflammation

Cerebral contusion is a severe medical problem affecting millions of people worldwide each year. There is an urgent need to understand the pathophysiological mechanism and to develop effective therapeutic strategy for this devastating neurological disorder. Intraparenchymal hemorrhage and post-traumatic inflammatory response induced by initial physical impact can aggravate microglia/macrophage activation and neuroinflammation which subsequently worsen brain pathology. We provide here a controlled cortical impact (CCI) protocol that can reproduce experimental cortical contusion in mice by using a pneumatic impactor system to deliver mechanical force with controllable magnitude and velocity onto the dural surface. This preclinical model allows researchers to induce moderately severe focal cerebral contusion in mice and to investigate a wide range of post-traumatic pathological progressions including hemorrhage contusion, microglia/macrophage activation, iron toxicity, axonal injury, as well as short-term and long-term neurobehavioral deficits. The present protocol can be useful for exploring the long-term effects of and potential interventions for cerebral contusion.

<meta charset="utf8"></head><body>Un modello preclinico di impatto corticale controllato per emorragia traumatica, contusione e neuroinfiammazione

Intraparenchymal hemorrhage and neuroinflammation accompanied by cerebral contusion can trigger severe secondary brain injury. This protocol details a mouse controlled cortical impact (CCI) model allowing researchers to study hemorrhage contusion and post-traumatic immune responses and explore potential therapeutics.