Endothelium-dependent vascular responses in 1,3-dipropyl-8-sulphophenylxanthine (DPSPX) hypertensive rats

• Type: Article in International Scientific Journal
• Date: 1997

Authors

Paiva, MQ (Author) Other; Santos, MJ (Author) Other; Albino Teixeira, A (Author) FMUP

Journal

Title: Journal of Pharmacy and Pharmacology

Vol. 49

Pages: 74-77

ISSN: 0022-3573

Publisher: Oxford University Press

Indexing

ISI Web of Knowledge - 8 Citations

Scopus - 6 Citations

Other information

Authenticus ID: P-001-CPV

DOI: 10.1111/j.2042-7158.1997.tb06755.x

Abstract (EN): The study was undertaken to test the endothelium-mediated vascular responses in rats rendered hypertensive by chronic administration of 1,3-dipropyl-8-suiphophenylxanthine (DPSPX). The relaxant effect of carbachol (an endothelium-dependent relaxing drug) and of sodium nitroprusside (an endothelium-independent relaxing drug) as well as the potentiation of the contractile effect of noradrenaline by N-G-nitro-L-arginine methyl ester (L-NAME) were compared in aortic rings from normotensive and DPSPX-hypertensive rats. Carbachol and sodium nitroprusside caused concentration-dependent relaxations in aortic rings precontracted by 1 mu M noradrenaline. The relaxant effect of carbachol was significantly reduced in tissues of DPSPX-hypertensive rats: the maximal relaxant effect being 86 +/- 3% and 64 +/- 4% (of the pre-existing tone) in normal and hypertensive rats, respectively, while there were no significant differences in the relaxant effect of sodium nitroprusside. L-NAME (100 mu M) significantly reduced the EC50 values of noradrenaline (3.71 +/- 0.28 times, n = 8 and 2.96 +/- 0.27 times, n = 7, in normal and hypertensive rats, respectively) and significantly enhanced the maximal contractile effect of noradrenaline (46 +/- 8%, n = 8 and 35+/-6%, n = 7, in normal and hypertensive rats respectively): the factors of reduction of EC50 values and the percentages of enhancement of the maximal contractile effect in the aorta of normal and hypertensive rats were not significantly different. The results obtained provide evidence of functional impairment of the endothelium in DPSPX-hypertensive rats.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 4