Ce travail a été soutenu par NIH R01 HD050901 à MCM et la bourse de recherche postdoctorale American Cancer Society # PF-05-041-01-DDC à TG.

<ol><li> Un poisson zèbre mâle sera disséqué en premier, suivi par un poisson femelle. Avant de commencer la dissection, anesthésier un poisson dans 0,2% tricaïne puis l&#39;euthanasier par incubation dans l&#39;eau glacée pendant 15 minutes. </li><li> Commencez par une légère tapotant le poisson sec sur une serviette en papier et en le plaçant sur un tapis de dissection. Extérieurement, le poisson zèbre ont dorsale, caudale et anale et jumelé nageoires pectorales et pelviennes (figure 1). <img src="/files/ftp_upload/1717/1717fig1.jpg" alt="Figure 1" /> Figure 1. Poissons mâles adultes avec des ailettes étiquetés. </li><li> Pin le poisson à travers le tapis disséquer la partie charnue de la queue et la partie ventrale de la cavité de l&#39;œil. </li><li> Snip la peau sur le ventre du poisson juste en avant de la nageoire anale. Coupez la peau et les muscles sous-jacents le long du ventre de la nageoire anale à l&#39;opercule (la couverture fort au cours des branchies) (figure 2, étape 1). <img src="/files/ftp_upload/1717/1717fig2.jpg" alt="Figure 2" /> Figure 2. Étapes de retirer la peau et les muscles de la paroi du corps pour exposer les organes internes. </li><li> Ensuite, retirez l&#39;opercule et la nageoire pectorale, y compris la ceinture scapulaire (l&#39;épaisseur, de la région osseuse à la base de la nageoire) (figure 2, étape 2). Coupez la peau et les muscles sous-jacents commencent au-dessus du présent exposé arrière des branchies le long du côté du poisson et ensuite jusqu&#39;à la nageoire anale (figure 2, étape 3). </li><li> Retirez soigneusement la peau et les muscles sous-jacents du côté du poisson. Beaucoup des organes internes sont maintenant visibles (figure 3). <img src="/files/ftp_upload/1717/1717fig3.jpg" alt="Figure 3" /> Figure 3. Adulte poissons mâles avec paroi musculaire du corps et enlevé permettant la visualisation des organes internes. </li><li> Les testicules sont longues, blanc, organes pairs qui sont attachés à la paroi dorsale du corps. Supprimer un testicule et le placer dans un plat de PBS. Examiner les testicules avec la lumière réfléchie de visualiser les tubules séminifères (Figure 4), qui contiennent des kystes aux divers stades de développement des cellules germinales à partir de spermatides spermatagonia (Leal et al., 2009). <img src="/files/ftp_upload/1717/1717fig4.jpg" alt="Figure 4" /> Figure 4. Dissection d&#39;un testicule. Les structures blanches arrondie sont les tubules séminifères. </li><li> Ensuite, retirez le système gastro-intestinal de la cavité abdominale du poisson. Le foie peut être identifié par sa grande taille, la morphologie lobé, de couleur tannish, et la vascularisation importante. La vésicule biliaire, d&#39;un vert translucide, sac rempli de liquide, et la rate, qui apparaît en rouge vif, se trouvent dans les viscères. </li><li> Séparée de l&#39;intestin du reste des organes et l&#39;étirer. L&#39;antérieure, les régions moyenne et postérieure de l&#39;intestin sont définis par la hauteur des plis épithéliaux (Wallace et al., 2005). </li><li> Placer un morceau de l&#39;intestin dans le PBS et d&#39;observer les replis épithéliaux en utilisant la lumière transmise. </li><li> Ensuite, examinez la vessie natatoire. La vessie natatoire se compose d&#39;une chambre postérieure, qui est relié à l&#39;œsophage par le conduit pneumatique, et une chambre antérieure, qui est relié à l&#39;oreille interne par l&#39;appareil de Weber (Finney et al., 2006). </li><li> Retirez et jetez la vessie natatoire. Détacher le poisson et re-broches c&#39;est la face ventrale à disséquer les reins, qui est située le long de la paroi dorsale du corps. Le rein est une structure associée rose translucide avec l&#39;aorte dorsale et les cellules pigmentées. Le rein est divisé en régions tête, le corps et la queue (figure 5). Disséquer un morceau du rein et de la placer dans du PBS. Démêler le tissu rénal de révéler les tubules rénaux. <img src="/files/ftp_upload/1717/1717fig5.jpg" alt="Figure 5" /> Figure 5. Localisation de la tête, le corps et la queue du rein le long de la paroi dorsale du corps. </li><li> Disséquer un poisson femelle. Comme décrit précédemment, euthanasier les poissons dans l&#39;eau glacée et sécher avant l&#39;épinglant sur le tapis de dissection. Enlevez la peau du côté des poissons comme précédemment démontré. L&#39;ovaire est une structure bilobée qui est suspendu dans la cavité du corps par un mésovarium vascularisé. </li><li> Retirer un lobe de l&#39;ovaire, le placer dans le PBS, et l&#39;examiner à la lumière transmise. Les ovocytes peuvent être taquiné dehors à l&#39;aide de fines aiguilles et ensuite mis en scène (figure 6, Selman et al., 1993). Phase I ovocytes sont environ 10 - 150 microns dans la taille et translucides. Etape II ovocytes sont environ 150 - 350 microns dans la taille et définie par l&#39;apparition de granules corticaux. Etape III ovocytes sont de 350 à 750 microns et sont opaques à cause de l&#39;accumulation de jaune d&#39;oeuf. Mature étape ovocytes IV et V sont translucides et généralement ne se trouve pas dans les ovaires des femelles qui ont récemment estimé. <img src="/files/ftp_upload/1717/1717fig6.jpg" alt="Figure 6" /> Figure 6. Étape en direct I, II, III et des ovocytes observé sous undisséquant microscope à lumière transmise. </li><li> Ensuite, disséquer le cœur du poisson. Le cœur est situé postérieure et ventrale de la branchie. Commencez par découper le cœur et l&#39;ensemble des tissus environnants et de la placer dans du PBS. Soigneusement disséquer loin le tissu entourant le coeur, en faisant attention à ne pas endommager l&#39;atrium délicate. </li><li> Placez le coeur disséqué dans la solution de Ringer à observer les battements du cœur. Identifier l&#39;atrium, ventricule et bulbe artériel (figure 7, Hu et al., 2001). <img src="/files/ftp_upload/1717/1717fig7.jpg" alt="Figure 7" /> Figure 7. Disséqué coeur adulte. </li><li> Remplissez la dissection en enlevant le cerveau des poissons. Commencez par désépinglage le poisson et enlever la tête avec une lame de rasoir. Retirez le tissu mou autant que possible de la face ventrale du crâne avec une pince. Retirez les yeux à l&#39;aide des ciseaux petit ressort. Pause ouvrir le crâne et enlever l&#39;os de la face ventrale du cerveau. Maintenant, placez la tête dans un plat de PBS et enlever les os du crâne à partir de la peau et la face dorsale du cerveau. </li><li> Identifier les bulbes olfactifs, télencéphale, habénula, tectum optique, le cervelet et le bulbe (figure 8, Wullimann et al, 1996;. Schilling, 2002). <img src="/files/ftp_upload/1717/1717fig8.jpg" alt="Figure 8" /> Figure 8. Disséqué le cerveau de poisson zèbre adulte. Vue dorsale, antérieure vers le haut. </li></ol>

<ol>
	<li>Finney, J. L., Robertson, G. N., McGee, C. A., Smith, F. M., Croll, R. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+and+Autonomic+Innervation+of+the+Swim+Bladder+in+the+Zebrafish+(Danio+rerio).">Structure and Autonomic Innervation of the Swim Bladder in the Zebrafish (Danio rerio).</a> J Comp Neurol. 495, 587-606 (2006).</li><li>Hu, N., Yost, H. J., Clark, E. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cardiac+morphology+and+blood+pressure+in+the+adult+zebrafish.">Cardiac morphology and blood pressure in the adult zebrafish.</a> Anat Rec. 264, 1-12 (2001).</li><li>Leal, M. C., Cardoso, E. R., N&#243;brega, R. H., Batlouni, S. R., Bogerd, J., Fran&#231;a, L. R., Schulz, R. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Histological+and+stereological+evaluation+of+zebrafish+(Danio+rerio)+spermatogenesis+with+an+emphasis+on+spermatogonial+generations.">Histological and stereological evaluation of zebrafish (Danio rerio) spermatogenesis with an emphasis on spermatogonial generations.</a> Biol Reprod. 81, 177-187 (2009).</li><li>Schilling, T. F., Nusslein-Volhard, C., Dahm, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+morphology+of+larval+and+adult+zebrafish.">The morphology of larval and adult zebrafish.</a> Zebrafish: A Practical Approach (The Practical Approach Series). , (2002).</li><li>Selman, K., Wallace, R., Sarka, A., Qi, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Stages+of+oocyte+development+in+the+Zebrafish,+Brachydanio+rerio.">Stages of oocyte development in the Zebrafish, Brachydanio rerio.</a> J. Morphol. 218, 203-224 (1993).</li><li>Wallace, K. N., Akhter, S., Smith, E. M., Lorent, K., Pack, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intestinal+growth+and+differentiation+in+zebrafish.">Intestinal growth and differentiation in zebrafish.</a> Mech Dev. 122, 157-173 (2005).</li><li>Wullimann, M. F., Rupp, B., Reichert, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Neuroanatomy of the zebrafish brain : a topological atlas. , (1996).</li></ol>

Expériences sur les animaux ont été effectuées en conformité avec les directives et règlements établis par l&#39;Université de Pennsylvanie des soins des animaux et du Comité institutionnel d&#39;utilisation.

Réactifs: 0,2% (éthyl 3-aminobenzoate) tricaïne 200 mg de poudre tricaïne 97,9 ml d&#39;eau JJ ~ 1 ml 1 M Tris (pH 9) Ajuster le pH à 7,0 Tampon phosphate salin (PBS) 4,0 g de NaCl 0,1 g de KCl 100 ml à 0,1 M de tampon PO 4, pH 7,3 150 ml dH 2 O Solution de Ringer 6.7g de NaCl 0.2g KCl 0.2g CaCl 2 Hepes 1,2 g 1 LH 2 O Ajuster le pH à 7,2 Equipement: Dissection plat avec tapis Sciences Electron Microscopy Le catalogue # 70540 Vannas des ciseaux à ressort Outils Fine Science Le catalogue # 91500-09

dissection of organs from the adult zebrafish

Au cours des 20 dernières années, le poisson-zèbre est devenu un organisme modèle puissant pour comprendre le développement des vertébrés et de la maladie. Bien que l&#39;analyse expérimentale de l&#39;embryon et la larve est vaste et la morphologie a été bien documenté, les descriptions de l&#39;anatomie de poisson zèbre pour adultes et des études sur le développement des structures pour adultes et les organes, ainsi que des techniques pour travailler avec les adultes sont absents. Les organes de la larve subissent d&#39;importants changements dans leur structure générale, la morphologie et la localisation anatomique lors de la larve de la transition pour adultes. Extérieurement, la larve transparente développe son modèle caractéristique de pigments pour adultes rayé et jumelé nageoires pelviennes, tandis qu&#39;à l&#39;intérieur, les organes subissent une croissance massive et le remodelage. En outre, le primordium bipotentielles gonades se développe en testicule ou l&#39;ovaire soit. Ce protocole identifie la plupart des organes de l&#39;adulte et démontre des méthodes pour la dissection du cerveau, les gonades, le système gastro-intestinal, le cœur et les reins du poisson-zèbre adulte. Les organes disséqués peut être utilisé pour l&#39;hybridation in situ, immunohistochimie, l&#39;histologie, l&#39;extraction d&#39;ARN, l&#39;analyse des protéines, et d&#39;autres techniques moléculaires. Ce protocole aidera à l&#39;élargissement des études dans le poisson zèbre pour inclure le remodelage des organes larvaires, la morphogenèse des organes spécifiques aux adultes et d&#39;autres enquêtes sur les systèmes d&#39;organes adultes.

Watch this Scientific Journal Video about Dissection of Organs from the Adult Zebrafish at JoVE.com

Dissection of Organs from the Adult Zebrafish

Ce protocole décrit une procédure pour identifier et disséquer les organes de l&#39;zèbre adulte.

Dissection d&#39;organes sur le poisson zèbre pour adultes

Over the last 20 years, the zebrafish has become a powerful model organism for understanding vertebrate development and disease.  Although experimental ...

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103.9K vues.  University of Pennsylvania-School of Medicine. Ce protocole décrit une procédure pour identifier et disséquer les organes de l'zèbre adulte.

Vidéo: Dissection of Organs from the Adult Zebrafish

Gross and Fine Dissection of Inner Ear Sensory Epithelia in Adult Zebrafish (Danio rerio)

Neurosensory epithelia in the inner ear are the crucial structures for hearing and balance functions. Therefore, it is important to understand the cellular and molecular features of the epithelia, which are mainly composed of two types of cells: hair cells (HCs) and supporting cells (SCs). Here we choose to study the inner ear sensory epithelia in adult zebrafish not only because the epithelial structures are highly conserved in all vertebrates studied, but also because the adult zebrafish is able to regenerate HCs, an ability that mammals lose shortly after birth. We use the inner ear of adult zebrafish as a model system to study the mechanisms of inner ear HC regeneration in adult vertebrates that could be helpful for clinical therapy of hearing/balance deficits in human as a result of HC loss.
Here we demonstrate how to do gross and fine dissections of inner ear sensory epithelia in adult zebrafish. The gross dissection removes the tissues surrounding the inner ear and is helpful for preparing tissue sections, which allows us to examine the detailed structure of the sensory epithelia. The fine dissection cleans up the non-sensory-epithelial tissues of each individual epithelium and enables us to examine the heterogeneity of the whole epithelium easily in whole-mount epithelial samples.

Gross and Fine Dissection of Inner Ear Sensory Epithelia in Adult Zebrafish Danio rerio

The inner ear sensory epithelium of adult zebrafish is a good model system for understanding the mechanisms of hair cell regeneration in adult vertebrates. This protocol demonstrates the fine dissection of the epithelia, through which we can get tissue samples for studying the regenerative events at cellular and subcellular levels.

Dissection fine et globale de l&#39;épithélium sensoriel de l&#39;oreille interne adultes poisson zèbre ( Danio rerio)

Neurosensory epithelia in the inner ear are the crucial structures for hearing and balance functions. Therefore, it is important to understand the ...

Recherche

Biologie

Dissection of Hippocampal Dentate Gyrus from Adult Mouse

The hippocampus is one of the most widely studied areas in the brain because of its important functional role in memory processing and learning, its remarkable neuronal cell plasticity, and its involvement in epilepsy, neurodegenerative diseases, and psychiatric disorders. The hippocampus is composed of distinct regions; the dentate gyrus, which comprises mainly granule neurons, and Ammon's horn, which comprises mainly pyramidal neurons, and the two regions are connected by both anatomic and functional circuits. Many different mRNAs and proteins are selectively expressed in the dentate gyrus, and the dentate gyrus is a site of adult neurogenesis; that is, new neurons are continually generated in the adult dentate gyrus. To investigate mRNA and protein expression specific to the dentate gyrus, laser capture microdissection is often used. This method has some limitations, however, such as the need for special apparatuses and complicated handling procedures. In this video-recorded protocol, we demonstrate a dissection technique for removing the dentate gyrus from adult mouse under a stereomicroscope. Dentate gyrus samples prepared using this technique are suitable for any assay, including transcriptomic, proteomic, and cell biology analyses. We confirmed that the dissected tissue is dentate gyrus by conducting real-time PCR of dentate gyrus-specific genes, tryptophan 2,3-dioxygenase (TDO2) and desmoplakin (Dsp), and Ammon's horn enriched genes, Meis-related gene 1b (Mrg1b) and TYRO3 protein tyrosine kinase 3 (Tyro3). The mRNA expressions of TDO2 and Dsp in the dentate gyrus samples were detected at obviously higher levels, whereas Mrg1b and Tyro3 were lower levels, than those in the Ammon's horn samples. To demonstrate the advantage of this method, we performed DNA microarray analysis using samples of whole hippocampus and dentate gyrus. The mRNA expression of TDO2 and Dsp, which are expressed selectively in the dentate gyrus, in the whole hippocampus of alpha-CaMKII+/- mice, exhibited 0.037 and 0.10-fold changes compared to that of wild-type mice, respectively. In the isolated dentate gyrus, however, these expressions exhibited 0.011 and 0.021-fold changes compared to that of wild-type mice, demonstrating that gene expression changes in dentate gyrus can be detected with greater sensitivity. Taken together, this convenient and accurate dissection technique can be reliably used for studies focused on the dentate gyrus.

A dissection technique for removal of the dentate gyrus from adult mouse under a stereomicroscope was demonstrated in this video-recorded protocol.

Dissection de l&#39;hippocampe gyrus denté de souris adulte

The hippocampus is one of the most widely studied areas in the brain because of its important functional role in memory processing and learning, its ...

Intraperitoneal Injection into Adult Zebrafish

A convenient method for chemically treating zebrafish is to introduce the reagent into the tank water, where it will be taken up by the fish. However, this method makes it difficult to know how much reagent is absorbed or taken up per fish. Some experimental questions, particularly those related to metabolic studies, may be better addressed by delivering a defined quantity to each fish, based on weight. Here we present a method for intraperitoneal (IP) injection into adult zebrafish. Injection is into the abdominal cavity, posterior to the pelvic girdle. This procedure is adapted from veterinary methods used for larger fish. It is safe, as we have observed zero mortality. Additionally, we have seen bleeding at the injection site in only 5 out of 127 injections, and in each of those cases the bleeding was brief, lasting several seconds, and the quantity of blood lost was small. Success with this procedure requires gentle handling of the fish through several steps including fasting, weighing, anesthetizing, injection, and recovery. Precautions are required to minimize stress throughout the procedure. Our precautions include using a small injection volume and a 35G needle. We use Cortland salt solution as the vehicle, which is osmotically balanced for freshwater fish. Aeration of the gills is maintained during the injection procedure by first bringing the fish into a surgical plane of anesthesia, which allows slow operculum movements, and second, by holding the fish in a trough within a water-saturated sponge during the injection itself. We demonstrate the utility of IP injection by injecting glucose and monitoring the rise in blood glucose level and its subsequent return to normal. As stress is known to increase blood glucose in teleost fish, we compare blood glucose levels in vehicle-injected and non-injected adults and show that the procedure does not cause a significant rise in blood glucose.

We demonstrate intraperitoneal injection into adult zebrafish. We use a 10 &mu;l NanoFil microsyringe controlled by a Micro4 controller and UltraMicroPump III. This demonstration includes the use of cold water as an anesthetic.

Injection intrapéritonéale en Zebrafish adultes

A convenient method for chemically treating zebrafish is to introduce the reagent into the tank water, where it will be taken up by the fish. However, ...

Dissection of Oenocytes from Adult Drosophila melanogaster

In Drosophila melanogaster, as in other insects, a waxy layer on the outer surface of the cuticle, composed primarily of hydrocarbon compounds, provides protection against desiccation and other environmental challenges. Several of these cuticular hydrocarbon (CHC) compounds also function as semiochemical signals, and as such mediate pheromonal communications between members of the same species, or in some instances between different species, and influence behavior. Specialized cells referred to as oenocytes are regarded as the primary site for CHC synthesis. However, relatively little is known regarding the involvement of the oenocytes in the regulation of the biosynthetic, transport, and deposition pathways contributing to CHC output. Given the significant role that CHCs play in several aspects of insect biology, including chemical communication, desiccation resistance, and immunity, it is important to gain a greater understanding of the molecular and genetic regulation of CHC production within these specialized cells. The adult oenocytes of D. melanogaster are located within the abdominal integument, and are metamerically arrayed in ribbon-like clusters radiating along the inner cuticular surface of each abdominal segment. In this video article we demonstrate a dissection technique used for the preparation of oenocytes from adult D. melanogaster. Specifically, we provide a detailed step-by-step demonstration of (1) how to fillet prepare an adult Drosophila abdomen, (2) how to identify the oenocytes and discern them from other tissues, and (3) how to remove intact oenocyte clusters from the abdominal integument. A brief experimental illustration of how this preparation can be used to examine the expression of genes involved in hydrocarbon synthesis is included. The dissected preparation demonstrated herein will allow for the detailed molecular and genetic analysis of oenocyte function in the adult fruit fly.

Dissection of Oenocytes from Adult Drosophila melanogaster

In insects, the oenocytes produce cuticular hydrocarbon compounds. These compounds protect against desiccation and facilitate chemical communication. Here we demonstrate a dissection technique used to isolate the oenocytes from adult Drosophila melanogaster, and illustrate how this preparation can be utilized to study genes involved in hydrocarbon synthesis.

Dissection de Oenocytes d&#39;adultes Drosophila melanogaster</em

In Drosophila melanogaster, as in other insects, a waxy layer on the outer surface of the cuticle, composed primarily of hydrocarbon compounds, provides ...

Transplantation of Cells Directly into the Kidney of Adult Zebrafish

Regenerative medicine based on the transplantation of stem or progenitor cells into damaged tissues has the potential to treat a wide range of chronic diseases1. However, most organs are not easily accessible, necessitating the need to develop surgical methods to gain access to these structures. In this video article, we describe a method for transplanting cells directly into the kidney of adult zebrafish, a popular model to study regeneration and disease2. Recipient fish are pre-conditioned by irradiation to suppress the immune rejection of the injected cells3. We demonstrate how the head kidney can be exposed by a lateral incision in the flank of the fish, followed by the injection of cells directly in to the organ. Using fluorescently labeled whole kidney marrow cells comprising a mixed population of renal and hematopoietic precursors, we show that nephron progenitors can engraft and differentiate into new renal tissue - the gold standard of any cell-based regenerative therapy. This technique can be adapted to deliver purified stem or progenitor cells and/or small molecules to the kidney as well as other internal organs and further enhances the zebrafish as a versatile model to study regenerative medicine.

Cell transplantation is an essential technique for studying tissue regeneration and for developing cell-based therapies of disease. We demonstrate here a microsurgical technique that permits the transplantation of genetically labeled cells directly into the kidney of adult zebrafish fish.

La transplantation de cellules directement dans le rein de poisson zèbre adulte

Regenerative medicine based on the transplantation of stem or progenitor cells into damaged tissues has the potential to treat a wide range of chronic ...

Dissection of the Adult Zebrafish Kidney

Researchers working in the burgeoning field of adult stem cell biology seek to understand the signals that regulate the behavior and function of stem cells during normal homeostasis and disease states. The understanding of adult stem cells has broad reaching implications for the future of regenerative medicine1. For example, better knowledge about adult stem cell biology can facilitate the design of therapeutic strategies in which organs are triggered to heal themselves or even the creation of methods for growing organs in vitro that can be transplanted into humans1. The zebrafish has become a powerful animal model for the study of vertebrate cell biology2. There has been extensive documentation and analysis of embryonic development in the zebrafish3. Only recently have scientists sought to document adult anatomy and surgical dissection techniques4, as there has been a progressive movement within the zebrafish community to broaden the applications of this research organism to adult studies. For example, there are expanding interests in using zebrafish to investigate the biology of adult stem cell populations and make sophisticated adult models of diseases such as cancer5. Historically, isolation of the zebrafish adult kidney has been instrumental for studying hematopoiesis, as the kidney is the anatomical location of blood cell production in fish6,7. The kidney is composed of nephron functional units found in arborized arrangements, surrounded by hematopoietic tissue that is dispersed throughout the intervening spaces. The hematopoietic component consists of hematopoietic stem cells (HSCs) and their progeny that inhabit the kidney until they terminally differentiate8. In addition, it is now appreciated that a group of renal stem/progenitor cells (RPCs) also inhabit the zebrafish kidney organ and enable both kidney regeneration and growth, as observed in other fish species9-11. In light of this new discovery, the zebrafish kidney is one organ that houses the location of two exciting opportunities for adult stem cell biology studies. It is clear that many outstanding questions could be well served with this experimental system. To encourage expansion of this field, it is beneficial to document detailed methods of visualizing and then isolating the adult zebrafish kidney organ. This protocol details our procedure for dissection of the adult kidney from both unfixed and fixed animals.
Dissection of the kidney organ can be used to isolate and characterize hematopoietic and renal stem cells and their offspring using established techniques such as histology, fluorescence activated cell sorting (FACS)11,12, expression profiling13,14, and transplantation11,15. 
We hope that dissemination of this protocol will provide researchers with the knowledge to implement broader use of zebrafish studies that ultimately can be translated for human application.

The zebrafish kidney is home to both renal and hematopoietic adult stem/progenitor cells, and represents an outstanding opportunity to study these cell types and their progeny in a vertebrate model organism. Here, we demonstrate a detailed dissection procedure that enables the researcher to identify and surgically remove the adult zebrafish kidney, which can be used for applications such as cell isolation, transplantation, and expression studies of kidney and/or blood cell populations.

Dissection du rein Zebrafish adultes

Researchers working in the burgeoning field of adult stem cell biology seek to understand the signals that regulate the behavior and function of stem ...

Heart Dissection in Larval, Juvenile and Adult Zebrafish, Danio rerio

Zebrafish have become a beneficial and practical model organism for the study of embryonic heart development (see recent reviews1-6), however, work examining post-embryonic through adult cardiac development has been limited7-10. Examining the changing morphology of the maturing and aging heart are restricted by the lack of techniques available for staging and isolating juvenile and adult hearts. In order to analyze heart development over the fish's lifespan, we dissect zebrafish hearts at numerous stages and photograph them for further analysis11. The morphological features of the heart can easily be quantified and individual hearts can be further analyzed by a host of standard methods. Zebrafish grow at variable rates and maturation correlates better with fish size than age, thus, post-fixation, we photograph and measure fish length as a gauge of fish maturation. This protocol explains two distinct, size dependent dissection techniques for zebrafish, ranging from larvae 3.5mm standard length (SL) with hearts of 100&mu;m ventricle length (VL), to adults, with SL of 30mm and VL 1mm or larger. Larval and adult fish have quite distinct body and organ morphology. Larvae are not only significantly smaller, they have less pigment and each organ is visually very difficult to identify. For this reason, we use distinct dissection techniques.
We used pre-dissection fixation procedures, as we discovered that hearts dissected directly after euthanization have a more variable morphology, with very loose and balloon like atria compared with hearts removed following fixation. The fish fixed prior to dissection, retain in vivo morphology and chamber position (data not shown). In addition, for demonstration purposes, we take advantage of the heart (myocardial) specific GFP transgenic Tg(myl7:GFP)twu34 (12), which allows us to visualize the entire heart and is particularly useful at early stages in development when the cardiac morphology is less distinct from surrounding tissues. Dissection of the heart makes further analysis of the cell and molecular biology underlying heart development and maturation using in situ hybridization, immunohistochemistry, RNA extraction or other analytical methods easier in post-embryonic zebrafish. This protocol will provide a valuable technique for the study of cardiac development maturation and aging.

Heart Dissection in Larval, Juvenile and Adult Zebrafish, Danio rerio

A clear, standardized method for dissection and isolation of the zebrafish heart at multiple developmental stages are described. Annotation and quantification techniques are also discussed.

Dissection du cœur chez les larves, le poisson zèbre juvéniles et adultes, Danio rerio</em

Zebrafish have become a beneficial and practical model organism for the study of embryonic heart development (see recent reviews1-6), however, work ...

In vivo Electroporation of Morpholinos into the Adult Zebrafish Retina

Many devastating inherited eye diseases result in progressive and irreversible blindness because humans cannot regenerate dying or diseased retinal neurons. In contrast, the adult zebrafish retina possesses the robust ability to spontaneously regenerate any neuronal class that is lost in a variety of different retinal damage models, including retinal puncture, chemical ablation, concentrated high temperature, and intense light treatment 1-8. Our lab extensively characterized regeneration of photoreceptors following constant intense light treatment and inner retinal neurons after intravitreal ouabain injection 2, 5, 9. In all cases, resident M&uuml;ller glia re-enter the cell cycle to produce neuronal progenitors, which continue to proliferate and migrate to the proper retinal layer, where they differentiate into the deficient neurons. 
	We characterized five different stages during regeneration of the light-damaged retina that were highlighted by specific cellular responses. We identified several differentially expressed genes at each stage of retinal regeneration by mRNA microarray analysis 10. Many of these genes are also critical for ocular development. To test the role of each candidate gene/protein during retinal regeneration, we needed to develop a method to conditionally limit the expression of a candidate protein only at times during regeneration of the adult retina. 
	Morpholino oligos are widely used to study loss of function of specific proteins during the development of zebrafish, Xenopus, chick, mouse, and tumors in human xenografts 11-14. These modified oligos basepair with complementary RNA sequence to either block the splicing or translation of the target RNA. Morpholinos are stable in the cell and can eliminate or "knockdown" protein expression for three to five days 12. 
	Here, we describe a method to efficiently knockdown target protein expression in the adult zebrafish retina. This method employs lissamine-tagged antisense morpholinos that are injected into the vitreous of the adult zebrafish eye. Using electrode forceps, the morpholino is then electroporated into all the cell types of the dorsal and central retina. Lissamine provides the charge on the morpholino for electroporation and can be visualized to assess the presence of the morpholino in the retinal cells. 
	Conditional knockdown in the retina can be used to examine the role of specific proteins at different times during regeneration. Additionally, this approach can be used to study the role of specific proteins in the undamaged retina, in such processes as visual transduction and visual processing in second order neurons.

In vivo Electroporation of Morpholinos into the Adult Zebrafish Retina

A method to conditionally knockdown a target protein&#x2019;s expression in the adult zebrafish retina is described, which involves intravitreally injecting antisense morpholinos and electroporating them into the retina. The resulting protein is knocked down for several days, which allows testing the protein&#x2019;s role in the regenerating or intact retina.

En électroporation in vivo de morpholinos dans la rétine de poisson zèbre adulte

Many devastating inherited eye diseases result in progressive and irreversible blindness because humans cannot regenerate dying or diseased retinal ...

In vivo Electroporation of Morpholinos into the Regenerating Adult Zebrafish Tail Fin

Certain species of urodeles and teleost fish can regenerate their tissues. Zebrafish have become a widely used model to study the spontaneous regeneration of adult tissues, such as the heart1, retina2, spinal cord3, optic nerve4, sensory hair cells5, and fins6.
The zebrafish fin is a relatively simple appendage that is easily manipulated to study multiple stages in epimorphic regeneration. Classically, fin regeneration was characterized by three distinct stages: wound healing, blastema formation, and fin outgrowth. After amputating part of the fin, the surrounding epithelium proliferates and migrates over the wound. At 33 &deg;C, this process occurs within six hours post-amputation (hpa, Figure 1B)6,7. Next, underlying cells from different lineages (ex. bone, blood, glia, fibroblast) re-enter the cell cycle to form a proliferative blastema, while the overlying epidermis continues to proliferate (Figure 1D)8. Outgrowth occurs as cells proximal to the blastema re-differentiate into their respective lineages to form new tissue (Figure 1E)8. Depending on the level of the amputation, full regeneration is completed in a week to a month.
The expression of a large number of gene families, including wnt, hox, fgf, msx, retinoic acid, shh, notch, bmp, and activin-betaA genes, is up-regulated during specific stages of fin regeneration9-16. However, the roles of these genes and their encoded proteins during regeneration have been difficult to assess, unless a specific inhibitor for the protein exists13, a temperature-sensitive mutant exists or a transgenic animal (either overexpressing the wild-type protein or a dominant-negative protein) was generated7,12. We developed a reverse genetic technique to quickly and easily test the function of any gene during fin regeneration.
Morpholino oligonucleotides are widely used to study loss of specific proteins during zebrafish, Xenopus, chick, and mouse development17-19. Morpholinos basepair with a complementary RNA sequence to either block pre-mRNA splicing or mRNA translation. We describe a method to efficiently introduce fluorescein-tagged antisense morpholinos into regenerating zebrafish fins to knockdown expression of the target protein. The morpholino is micro-injected into each blastema of the regenerating zebrafish tail fin and electroporated into the surrounding cells. Fluorescein provides the charge to electroporate the morpholino and to visualize the morpholino in the fin tissue.
This protocol permits conditional protein knockdown to examine the role of specific proteins during regenerative fin outgrowth. In the Discussion, we describe how this approach can be adapted to study the role of specific proteins during wound healing or blastema formation, as well as a potential marker of cell migration during blastema formation.

In vivo Electroporation of Morpholinos into the Regenerating Adult Zebrafish Tail Fin

We describe a method to conditionally knockdown the expression of a target protein during adult zebrafish fin regeneration. This technique involves micro-injecting and electroporating antisense oligonucleotide morpholinos into fin tissue, which allows testing the protein&#x2019;s role in various stages of fin regeneration, including wound healing, blastema formation, and regenerative outgrowth.

En électroporation in vivo de morpholinos dans la régénération des adultes Zebrafish Tail Fin

Certain species of urodeles and teleost fish can regenerate their tissues. Zebrafish have become a widely used model to study the spontaneous regeneration ...

Gavaging Adult Zebrafish

The zebrafish has become an important in vivo model in biomedical research. Effective methods must be developed and utilized to deliver compounds or agents in solutions for scientific research. Current methods for administering compounds orally to adult zebrafish are inaccurate due to variability in voluntary consumption by the fish. A gavage procedure was developed to deliver precise quantities of infectious agents to zebrafish for study in biomedical research. Adult zebrafish over 6 months of age were anesthetized with 150 mg/L of buffered MS-222 and gavaged with 5 &mu;l of solution using flexible catheter implantation tubing attached to a cut 22-G needle tip. The flexible tubing was lowered into the oral cavity of the zebrafish until the tip of the tubing extended past the gills (approximately 1 cm). The solution was then injected slowly into the intestinal tract. This method was effective 88% of the time, with fish recovering uneventfully. This procedure is also efficient as one person can gavage 20-30 fish in one hour. This method can be used to precisely administer agents for infectious diseases studies, or studies of other compounds in adult zebrafish.

The increasing use of zebrafish as an animal model requires the development of effective methods for the delivery of known quantities of compounds and solutions. The gavage procedure described below allows for the oral delivery of precise volumes of solution reliably, safely and efficiently to adult zebrafish.

Gavage poisson zèbre pour adultes

The zebrafish has become an important in vivo model in biomedical research. Effective methods must be developed and utilized to deliver compounds or ...