Journal article
Enhanced Responses of the Basilar Artery to Activation of Endothelin-B Receptors in Stroke-Prone Spontaneously Hypertensive Rats
Hypertension (Dallas, Tex. 1979), Vol.25(4), pp.490-494
04/1995
DOI: 10.1161/01.HYP.25.4.490
PMID: 7721388
Abstract
We tested the hypothesis that responses of the basilar artery to selective activation of endothelin-B receptors are altered during chronic hypertension. Using a cranial window in anesthetized rats, we examined responses of the basilar artery to a selective endothelin-B receptor agonist, IRL 1620, in stroke-prone spontaneously hypertensive rats (SHRSP). Under control conditions, baseline basilar artery diameter was smaller in SHRSP (196 plus/minus 8 micro meter [mean plus/minus SEM]) than in normotensive Wistar-Kyoto rats (WKY) (245 plus/minus 9 micro meter, P < .05). Topical application of IRL 1620 (10 () mol/L) dilated the basilar artery by 27 plus/minus 5% in WKY and 56 plus/minus 4% in SHRSP (P < .05). Dilatation of the basilar artery in response to sodium nitroprusside was similar in WKY and SHRSP. In contrast, acetylcholine-induced vasodilatation in SHRSP was markedly impaired. N -Nitro-L-arginine methyl ester and N -nitro-L-arginine, inhibitors of nitric oxide synthase, inhibited IRL 1620-induced vasodilatation in WKY. Neither N -nitro-L-arginine methyl ester nor indomethacin attenuated vasodilatation produced by IRL 1620 in SHRSP. The major finding is that dilator responses of the basilar artery to selective activation of endothelin-B receptors are paradoxically enhanced in SHRSP compared with WKY. Dilator responses of the basilar artery to endothelin-B receptor activation are mediated by endothelium-derived relaxing factor in WKY. In contrast, responses to activation of endothelin receptors in SHRSP do not depend on the production of nitric oxide or prostanoids. (Hypertension. 1995;25[part 1]:490-494.)
Details
- Title: Subtitle
- Enhanced Responses of the Basilar Artery to Activation of Endothelin-B Receptors in Stroke-Prone Spontaneously Hypertensive Rats
- Creators
- Takanari Kitazono - Received December 13, 1993; first decision February 23, 1994; revision accepted December 21, 1994. From the Departments of Internal Medicine and Pharmacology, Center on Aging and Cardiovascular Center, University of Iowa College of Medicine; and the Veterans Administration Medical Center, Iowa City. Correspondence to Donald D. Heistad, MD, Department of Internal Medicine, University of Iowa College of Medicine, Iowa City, IA 52242Donald D HeistadFrank M Faraci
- Resource Type
- Journal article
- Publication Details
- Hypertension (Dallas, Tex. 1979), Vol.25(4), pp.490-494
- Publisher
- American Heart Association, Inc
- DOI
- 10.1161/01.HYP.25.4.490
- PMID
- 7721388
- ISSN
- 0194-911X
- eISSN
- 1524-4563
- Language
- English
- Date published
- 04/1995
- Academic Unit
- Cardiovascular Medicine; Neuroscience and Pharmacology; Internal Medicine
- Record Identifier
- 9984040547302771
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