Name: Forfatter Spotlight: Fordele ved tryk-volumen-sløjfemålingsmetode i kardiovaskulær forskning
Uploaded: 2024-01-12T13:25:00
Description: Watch this Scientific Journal Video about Author Spotlight: Advantages of Pressure-Volume Loop Measurement Method in Cardiovascular Research at JoVE.com

Dette arbejde blev støttet af Sichuan Provincial Major R&D Project (2022YFS043) og Chengdu University of Traditional Chinese Medicine Youth Foundation Advancement Talent Special Project (QJJJ2022029).

Dyreprotokollen blev gennemgået og godkendt af Chengdu University of Traditional Chinese Medicine Experimental Animal Welfare Ethics Committee (Record No. 2023-04). Hanrotter fra Sprague Dawley (SD) (280 ± 20 g, 8-10 uger gamle) blev anvendt til denne undersøgelse. Rotterne blev holdt i et dyrekammer og var frie til at drikke og spise.
1. Forberedelse af opløsning
<ol><li>Forbered 0,9% NaCl-opløsning, der skal bruges til at holde arbejdsområdet tilstrækkeligt fugtigt....

Overvågning af hjertefunktion hos rotter ved hjælp af tryk-volumen konduktansteknikken

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A., Townsend, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Early+right+ventricular+fibrosis+and+reduction+in+biventricular+cardiac+reserve+in+the+dystrophin-deficient+mdx+heart.">Early right ventricular fibrosis and reduction in biventricular cardiac reserve in the dystrophin-deficient mdx heart.</a> Am J Physiol Heart Circ Physiol. 308 (4), H303-H315 (2015).</li><li>Alaerts, G., 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=Exploratory+analysis+of+chromatographic+fingerprints+to+distinguish+rhizoma+Chuanxiong+and+rhizoma+Ligustici.">Exploratory analysis of chromatographic fingerprints to distinguish rhizoma Chuanxiong and rhizoma Ligustici.</a> J Chromatogr A. 1217 (49), 7706-7716 (2010).</li><li>Serreli, G., 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=Ferulic+acid+derivatives+and+Avenanthramides+modulate+endothelial+function+through+maintenance+of+nitric+oxide+balance+in+HUVEC+cells.">Ferulic acid derivatives and Avenanthramides modulate endothelial function through maintenance of nitric oxide balance in HUVEC cells.</a> Nutrients. 13 (6), 2026 (2021).</li><li>Li, D., 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=Ferulic+acid:+A+review+of+its+pharmacology,+pharmacokinetics+and+derivatives.">Ferulic acid: A review of its pharmacology, pharmacokinetics and derivatives.</a> Life Sci. 284, 119921 (2021).</li><li>Monceaux, K., 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=Ferulic+acid,+Pterostilbene,+and+Tyrosol+protect+the+heart+from+ER-stress-induced+injury+by+activating+SIRT1-dependent+deacetylation+of+eIF2&#945;.">Ferulic acid, Pterostilbene, and Tyrosol protect the heart from ER-stress-induced injury by activating SIRT1-dependent deacetylation of eIF2&#945;.</a> Int J Mol Sci. 23 (12), 6628 (2022).</li><li>Liu, Z., 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=N-terminal+truncated+peroxisome+proliferator-activated+receptor-&#947;+coactivator-1&#945;+alleviates+phenylephrine-induced+mitochondrial+dysfunction+and+decreases+lipid+droplet+accumulation+in+neonatal+rat+cardiomyocytes.">N-terminal truncated peroxisome proliferator-activated receptor-&#947; coactivator-1&#945; alleviates phenylephrine-induced mitochondrial dysfunction and decreases lipid droplet accumulation in neonatal rat cardiomyocytes.</a> Mol Med Rep. 18 (2), 2142-2152 (2018).</li><li>Sun, Y., 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=Shuangxinfang+prevents+S100A9-induced+macrophage/microglial+inflammation+to+improve+cardiac+function+and+depression-like+behavior+in+rats+after+acute+myocardial+infarction.">Shuangxinfang prevents S100A9-induced macrophage/microglial inflammation to improve cardiac function and depression-like behavior in rats after acute myocardial infarction.</a> Front Pharmacol. 13, 832590 (2022).</li><li>Panneerselvam, 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=Ferulic+acid+attenuates+arsenic-induced+cardiotoxicity+in+rats.">Ferulic acid attenuates arsenic-induced cardiotoxicity in rats.</a> Biotechnol Appl Biochem. 67 (2), 186-195 (2020).</li><li>Hsueh, B., 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=Cardiogenic+control+of+affective+behavioural+state.">Cardiogenic control of affective behavioural state.</a> Nature. 615 (7951), 292-299 (2023).</li><li>Townsend, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Measuring+pressure+volume+loops+in+the+mouse.">Measuring pressure volume loops in the mouse.</a> J Vis Exp. (111), e53810 (2016).</li><li>Bastos, M. B., 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=Invasive+left+ventricle+pressure-volume+analysis:+overview+and+practical+clinical+implications.">Invasive left ventricle pressure-volume analysis: overview and practical clinical implications.</a> Eur Heart J. 41 (12), 1286-1297 (2020).</li><li>Wang, L. Y., 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=Effects+of+ferulic+acid+on+antioxidant+activity+in+Angelicae+Sinensis+Radix,+Chuanxiong+Rhizoma,+and+their+combination.">Effects of ferulic acid on antioxidant activity in Angelicae Sinensis Radix, Chuanxiong Rhizoma, and their combination.</a> Chin J Nat Med. 13 (6), 401-408 (2015).</li><li>Liu, Z., 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=Ferulic+acid+increases+intestinal+Lactobacillus+and+improves+cardiac+function+in+TAC+mice.">Ferulic acid increases intestinal Lactobacillus and improves cardiac function in TAC mice.</a> Biomed Pharmacother. 120, 109482 (2019).</li><li>Baan, J., 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=Continuous+measurement+of+left+ventricular+volume+in+animals+and+humans+by+conductance+catheter.">Continuous measurement of left ventricular volume in animals and humans by conductance catheter.</a> Circulation. 70 (5), 812-823 (1984).</li><li>Dam Lyhne, M., 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=Effects+of+mechanical+ventilation+versus+apnea+on+bi-ventricular+pressure-volume+loop+recording.">Effects of mechanical ventilation versus apnea on bi-ventricular pressure-volume loop recording.</a> Physiol Res. 71 (1), 103-111 (2022).</li></ol>

Det er vigtigt at vedtage en rationel doseringsstrategi for forskellige tilstande af hjertefunktion. Tryk-volumen konduktanskateterteknikken er den mest intuitive måde at studere venstre ventrikelfunktion5 på. Denne metode gør det muligt at undersøge virkningerne af lægemidler på hjertefunktionen fra et helt perspektiv. Vi beskriver de forskellige stadier af eksperimentet i detaljer. Dette vil give en vis facilitet til undersøgelse af hjertefunktion.
Trykvolumenl...

Hjerte-kar-sygdomme har den højeste dødelighed i verden1. Dens årsager omfatter koronararteriestenose (myokardieiskæmi), koronararterieblokering (myokardieinfarkt) og iskæmi-reperfusionsskade2. Da hjertet er i en konstant systolisk og diastolisk cyklus, er det en af de mest energikrævende dele af kroppen. Derfor, når koronararterierne har svært ved at opretholde tilstrækkelig energi og ilt, falder hjertefunktionen uundgåeligt, hvilket har en negativ indvirkning på andre organer 3,4. Hjertet er et kraftcenter i kredsløbssystemet, og hjertefunktionen skal vurderes rationelt.
Vurdering af hjertefunktion ved ventrikulært tryk og volumenforhold anses for at være en omfattende metode5. Ændringer i ventrikulært tryk og volumen i realtid under hele hjertecyklussen udgør trykvolumensløjfen. Den ventrikulære trykvolumensløjfe tillader kvantitativ analyse af hjertefunktion og reservekapacitet med hensyn til forskellige faser og energier i ventriklen. Den normale ventrikel har et lille endesystolisk volumen med godt slagarbejde og effektivitet 5,6,7.
Trykvolumenledningskateterteknikken er en invasiv metode til påvisning af status for venstre ventrikel. Det kan bruges til at opnå en kontinuerlig realtids trykvolumensløjfe8. Trykvolumetriske ledningsevnekatetre er effektive værktøjer, og lydhåndteringsprocedurer er afgørende for reproducerbare og pålidelige resultater, herunder in vivo-analyse af myokardieparallel ledningsevne under saltvandskalibrering og in vitro-måling af blodledningsevne i kuvettekalibrering3.
Ferulinsyre (FA), en phenolsyre, er bredt udbredt i planteriger som Avena sativa og Ligusticum chuanxiong hort 9,10. Ferulinsyre har farmakologiske virkninger af at sænke blodtrykket og arytmi. FA er et bioaktivt naturprodukt med flere funktioner. FA kan modstå oxidativ skade, reducere inflammatoriske reaktioner, hæmme blodpladeaggregering og forhindre koronar hjertesygdom og aterosklerose11. Imidlertid har de fleste undersøgelser af ferulinsyre fokuseret på et aspekt af hjertet, og sjældent er virkningerne af ferulinsyre blevet evalueret i kredsløbssystemet 12,13,14,15. Her beskriver vi en lukket brysttilgang til isofluranbedøvelse kombineret med ketamin (50 mg/kg) med fokus på hjertets respons på ferulinsyreopløsning under jugular veneinjektion.
Vi vil beskrive den komplette procedure for brug af værktøjet under lukkede brystforhold, herunder opløsningsforberedelse, forberedelse af transduceren, præeksperimentel rotteforberedelse, kateterindsættelse i højre halspulsåre og dataanalyse. Eksperimentets varighed er normalt mindre end 4 timer, og det bestemmes af de forskellige eksperimentelle protokoller. I et enkelt eksperiment kan vi få detaljerede hjerteoplysninger såsom venstre ventrikeltryk, volumen og puls.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>1 mL syringe</td>
			<td>Sartorius AG, Germany</td>
			<td>-</td>
			<td></td>
		</tr>
		<tr>
			<td>Animal temperature maintainer</td>
			<td>Rayward Life Technology Co., Ltd</td>
			<td>69020</td>
			<td></td>
		</tr>
		<tr>
			<td>Dual Bio Amp</td>
			<td>Millar, Inc., USA</td>
			<td>DA-100</td>
			<td></td>
		</tr>
		<tr>
			<td>Enzyme-Active Powdered Detergent</td>
			<td>Alconox Inc., USA</td>
			<td>1104</td>
			<td></td>
		</tr>
		<tr>
			<td>Ferulic acid</td>
			<td>&#160;Macklin Biochemical Co., Ltd,Shanghai, China</td>
			<td>F900027</td>
			<td></td>
		</tr>
		<tr>
			<td>Mikro-Tip Catheter Transducers, SPR-838NR</td>
			<td>Millar, Inc., USA</td>
			<td>SPR-838NR</td>
			<td></td>
		</tr>
		<tr>
			<td>Millar Miro-Tip Pressure Volume (MPVS) Ultra</td>
			<td>Millar, Inc., USA</td>
			<td>SPR-869</td>
			<td></td>
		</tr>
		<tr>
			<td>Pet electric clippers</td>
			<td>Jinyun County New Concept Home Supplies Co., Ltd.</td>
			<td>&#160;-</td>
			<td></td>
		</tr>
		<tr>
			<td>Power Lab 8 / 35</td>
			<td>Millar, Inc., USA</td>
			<td>PL3508</td>
			<td></td>
		</tr>
		<tr>
			<td>Sodium Chloride, NaCl</td>
			<td>&#160;Kelong Chemical Reagent, Chengdu, China</td>
			<td>KX829463</td>
			<td></td>
		</tr>
		<tr>
			<td>Veet hair removal cream</td>
			<td>Shanghai Songqi E-commerce Co., Ltd.</td>
			<td>3226470</td>
			<td></td>
		</tr>
	</tbody>
</table>

real-time detection of ferulic acid effects on rat left ventricle using pressure-volume conductivity catheter

Nedsat hjertefunktion kan have en negativ indvirkning på andre organer. Forholdet mellem venstre ventrikel og tryk og volumen anses for at være en gyldig metode til evaluering af hjertefunktionen. Realtidsovervågning af hjertefunktionen er vigtig for lægemiddelevaluering. Under lukkede brystforhold kommer miniaturetransduceren, som er en vigtig bestanddel af trykvolumenkateteret, ind i rottens venstre ventrikel gennem højre halspulsåre. Enheden visualiserer ændringerne i hjertefunktionen under eksperimentet i form af en trykvolumensløjfe. Det faktiske volumen af ventriklen beregnes ved at ændre blodets ledningsevne ved at injicere 50 μL af en 20% natriumchloridopløsning i rottens venstre jugularvene. Det faktiske volumen af rottens ventrikelhulrum beregnes ved at måle blodets ledningsevne i et kendt volumen ved hjælp af et konduktanskateter med trykvolumen. Denne protokol giver mulighed for kontinuerlig observation af virkningerne af lægemidler på hjertet og vil fremme begrundelsen for brugen af specialiserede etniske lægemidler i hjerte-kar-sygdomme.

Cardiovascular disease has the highest mortality rate in the world1. Its causes include coronary artery stenosis (myocardial ischemia), coronary artery blockage (myocardial infarction), and ischemia-reperfusion injury2. As the heart is in a constant systolic and diastolic cycle, it is one of the most energy-demanding parts of the body. Therefore, when the coronary arteries have difficulty maintaining sufficient energy and oxygen, cardiac function inevitably decreases, which has a negative impact on other organs3,4. The heart is a powerhouse in the circulatory system, and cardiac function needs to be assessed rationally.
Assessment of cardiac function by ventricular pressure and volume relationships is considered to be a comprehensive method5. Real-time changes in ventricular pressure and volume during the complete cardiac cycle make up the pressure-volume loop. The ventricular pressure-volume loop allows quantitative analysis of cardiac function and reserve capacity in terms of different phases and energies of the ventricle. The normal ventricle has a small end-systolic volume with good beat work and efficiency5,6,7.
The pressure-volume conduction catheter technique is an invasive method for detecting the status of the left ventricle. It can be used to obtain a continuous real-time pressure-volume loop8. Pressure volumetric conductivity catheters are powerful tools, and sound handling procedures are essential for reproducible and reliable results, including in vivo analysis of myocardial parallel conductivity during saline calibration and in vitro measurement of blood conductivity in cuvette calibration3.
Ferulic acid (FA), a phenolic acid, is widely distributed in plant kingdoms such as Avena sativa and Ligusticum chuanxiong hort9,10. Ferulic acid has pharmacological effects of lowering blood pressure and arrhythmia. FA is a bioactive natural product with multiple functions. FA can resist oxidative damage, reduce inflammatory responses, inhibit platelet aggregation, and prevent coronary heart disease and atherosclerosis11. However, most studies on ferulic acid have focused on one aspect of the heart and rarely have the effects of ferulic acid been evaluated in the circulatory system12,13,14,15. Here we describe a closed-chest approach to isoflurane anesthesia combined with Ketamine (50 mg/kg) with a focus on the cardiac response to ferulic acid solution during jugular vein injection.
We will describe the complete procedure for using the tool under closed-chest conditions, including solution preparation, preparation of the transducer, pre-experimental rat preparation, catheter insertion into the right carotid artery and data analysis. The duration of the experiment is usually less than 4 h and it is determined by the different experimental protocols. In a single experiment, we can obtain detailed cardiac information such as left ventricular pressure, volume, and heart rate.

Forfatter Spotlight: Fordele ved tryk-volumen-sløjfemålingsmetode i kardiovaskulær forskning

Påvisning i realtid af ferulinsyrevirkninger på rottens venstre ventrikel ved hjælp af ledningsevnekateter med trykvolumen

Anesthesia is an unavoidable issue in animal experiments. In this experiment, the different levels of anesthesia have a significant impact on the experimental results. This pressure-volume loop measurement method is easier to learn compared to the open-chest method, including fewer experimental tools and less learning time for experimenters.Our lab will research traditional Chinese medicine's effects and on cardiovascular diseases, exploring its extensive but not fully understood impact on heart health.

Hver test (n = 3) var baseret på indtræden af et tryk-volumen ledningsevnekateter i venstre ventrikel. Der er betydelige signalændringer, såsom en markant stigning i trykområdet, da kateteret kommer ind i venstre ventrikel fra halspulsåren (figur 1). Grafisk analyse af tryk-volumen-forholdet afsluttes ved at plotte volumen (μL) på Y-aksen og trykket (mmHg) på X-aksen. Rottens venstre ventrikeltryk var inden for 10-105 mmHg, og volumenets konduktansværdier var inden for 65-115 μL.<...

Watch this Scientific Journal Video about Author Spotlight: Advantages of Pressure-Volume Loop Measurement Method in Cardiovascular Research at JoVE.com

Denne protokol beskriver en metode til måling af venstre ventrikeltryk og volumen ved hjælp af tryk-volumen-konduktansteknikken. Denne metode muliggør kontinuerlig realtidsovervågning af virkningerne af lægemidler på hjertet.

Decreased cardiac function can have a negative impact on other organs. The left ventricular pressure-volume relationship is considered to be a valid ...

Anæstesi er et uundgåeligt problem i dyreforsøg. I dette eksperiment har de forskellige niveauer af anæstesi en betydelig indvirkning på de eksperimentelle resultater. Denne trykvolumen-loop-målemetode er lettere at lære sammenlignet med metoden med åben bryst, herunder færre eksperimentelle værktøjer og mindre læringstid for eksperimenter.Vores laboratorium vil undersøge traditionel kinesisk medicins virkninger og på hjerte-kar-sygdomme og udforske dens omfattende, men ikke fuldt forståede indvirkning på hjertesundheden.

real-time-detection-ferulic-acid-effects-on-rat-left-ventricle-using

Research

JoVE Journal

Medicine

Real-Time Detection of Ferulic Acid Effects on Rat Left Ventricle Using Pressure-Volume Conductivity Catheter

Decreased cardiac function can have a negative impact on other organs. The left ventricular pressure-volume relationship is considered to be a valid method for evaluating cardiac function. Real-time monitoring of cardiac function is important for drug evaluation. Under closed-chest conditions, the miniature transducer, which is an important component of the pressure-volume catheter, enters the left ventricle of the rat through the right carotid artery. The device visualizes the changes in cardiac function during the experiment in the form of a pressure-volume loop. The actual volume of the ventricle is calculated by altering the conductivity of the blood by injecting 50 &#181;L of a 20% sodium chloride solution into the rat's left jugular vein. The actual volume of the rat's ventricular cavity is calculated by measuring the conductivity of the blood in a known volume using a pressure-volume conductance catheter. This protocol allows for continuous observation of the effects of drugs on the heart and will promote the rationale for the use of specialty ethnic drugs in cardiovascular disease.

This protocol describes a method for measuring left ventricular pressure and volume using the pressure-volume conductance technique. This method enables continuous real-time monitoring of the effects of drugs on the heart.