These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.
Pubmed for Handhelds
PUBMED FOR HANDHELDS
Search MEDLINE/PubMed
Title: Depressor responses to endothelin-1 into the superior colliculus of rats: predominant role of endothelin ET(B) receptors. Author: D'Amico M, Di Filippo C, Rossi F. Journal: Eur J Pharmacol; 1998 Apr 17; 347(1):71-5. PubMed ID: 9650850. Abstract: We used in vitro autoradiography to identify the endothelin-1 receptor subtype(s) in the superficial gray layer of the superior colliculus of rats. These studies showed dense binding of (3-[125I]iodotyrosyl13)-[Ala11,15]Ac-endothelin-1-(6-2 1) (BQ3020) (for endothelin ETB receptors), while tissues incubated with [125I]( N-(hexahydro-1-azepinyl)carbonyl)L-Leu(1-Me)D-Trp-D-Tyr (PD151242) (for endothelin ETA receptors) had low binding. In addition, we examined the effects of the endothelin receptor antagonists, (R)-2-[(R)-2-[(S)-2-[[1-hexahydro-1H-azepinyl)]carbonyl]amino-4-++ +methylpentanoyl]-amino-3-(2-pyridyl)propionic acid (FR139317) (endothelin ETA receptor-selective), (+)-(1S,2R,3S)-3-(2-carboxymethoxy-4-methoxyphenyl)-1-(3,4-methylenediox yphenyl)-5-(prop-1-yloxy)indane-2-carboxylic acid (SB209670) (endothelin ETA/ETB receptor non-selective) and N-cis-2,6-dimethylpiperidinocarbonyl-L-gamma-metLeu-D-1-m ethoxycarbonylTrp-D-Nle (BQ-788) (endothelin ETB receptor-selective antagonist) on the responses following administration of endothelin-1 into the superficial layer of the superior colliculus. Endothelin-1 microinjected into this nucleus causes decreases in blood pressure (control, 109 +/- 6 mmHg, n = 6; endothelin-1, 72 +/- 5 mmHg, n = 6). These effects were greatly reduced by pre-administration into the superior colliculus of BQ-788 (5 nmol/rat) or SB209670 (3 nmol/rat) (94 +/- 5 and 98 +/- 6%, respectively) but were not affected by FR139317 (5 nmol/rat) (6 +/- 3%). Therefore, together with autoradiography, our functional data showed that endothelin ETB receptors are the predominant mediators of depressor responses induced by endothelin-1 injected into the superior colliculus of the rat.[Abstract] [Full Text] [Related] [New Search]