spacer gif spacer gif spacer gif spacer gif spacer gif
QUICK SEARCH:   [advanced]


spacer gif
     Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents    

This Article
Right arrow Figures Only
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Schwerte, T.
Right arrow Articles by Fritsche, R.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Schwerte, T.
Right arrow Articles by Fritsche, R.
Social Bookmarking
Add to CiteULike   Add to Complore   Add to Connotea   Add to Del.icio.us   Add to Digg   Add to Reddit   Add to Technorati   Add to Twitter  
What's this?
The Journal of Experimental Biology 205, 225-232 (2002)
© 2002 The Company of Biologists Limited

Vascular control in larval Xenopus laevis: the role of endothelial-derived factors

Thorsten Schwerte*, Eva Printz and Regina Fritsche

Department of Zoophysiology, University of Göteborg, Sweden

*Present address: Institut für Zoologie und Limnologie, Leopold-Franzens-Universität, Techniker Straße 25, A-6020 Innsbruck, Austria (e-mail: thorsten.schwerte{at}uibk.ac.at)

Accepted 8 November 2001

We used novel digital contrasting methods to measure the effects of endothelin-1 (ET-1, 10–6 to 10–8 mol l–1), the nitric-oxide-releasing agent sodium nitroprusside (SNP, 10–2 mol l–1) and N{omega}-nitro-L-arginine methyl ester hydrochloride (L-NAME, 10–4 mol l–1), a non-selective inhibitor of nitric oxide synthase, on the diameter of tiny arteries and veins of the head in anaesthetized Xenopus laevis tadpoles (stage NF 50–53). Perfusion of the main artery and vein supplying the head with ET-1 caused an immediate, significant and dose-dependent vasoconstriction. While preincubation with L-NAME caused no significant change in vessel diameter, the constriction provoked by subsequent endothelin administration was significantly enhanced. Application of SNP caused a vasodilation that was significant only after preconstriction with ET-1 (10–6 mol l–1). Our results provide strong evidence that the vasculature of developing Xenopus laevis tadpoles (NF stage 50–53) is influenced by endogenously released nitric oxide and endothelin. Vasoactive mediators released from vascular endothelial cells could be particularly important in vascular control in early embryos when the autonomic innervation is undifferentiated, poorly developed or even absent.

Key words: video image analysis, digital motion analysis, microcirculation, cardiovascular system, development, endothelin, nitric oxide, Xenopus laevis, endothelial cell.


Add to CiteULike CiteULike   Add to Complore Complore   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us   Add to Digg Digg   Add to Reddit Reddit   Add to Technorati Technorati   Add to Twitter Twitter    What's this?




© The Company of Biologists Ltd 2002