Expression of myogenic constrictor tone in the aorta of hypertensive rats.

Content Provider	Semantic Scholar
Author	Rapacon-Baker, M. M. Zhang, Fangyi Pucci, Michael L. Guan, Hong-Zhi Nasjletti, Alberto
Copyright Year	2001
Abstract	We investigated the effect of intraluminal pressure or stretch on the development of tone in the descending thoracic aorta from rats with aortic coarctation-induced hypertension of 7-14 days duration. Increments of pressure >100 mmHg decreased the diameter of thoracic aortas from hypertensive but not from normotensive rats. The pressure-induced constriction was not demonstrable in vessels superfused with calcium-free buffer. Stretched rings of aorta from hypertensive rats exhibited a calcium-dependent constrictor tone accompanied by elevated calcium influx that varied in relation to the degree of stretch. Blockers of L-type calcium channels and inhibitors of protein kinase C reduced both basal tone and calcium influx in aortic rings of hypertensive rats. Hence, the thoracic aorta of hypertensive rats expresses a pressure- and stretch-activated constrictor mechanism that relies on increased calcium influx through L-type calcium channels via a protein kinase C-regulated pathway. The expression of such a constrictor mechanism is suggestive of acquired myogenic behavior.
Starting Page	537
Ending Page	544
Page Count	8
File Format	PDF HTM / HTML
Alternate Webpage(s)	http://ajpregu.physiology.org/content/ajpregu/280/4/r968.full.pdf
PubMed reference number	11247816v1
Volume Number	280
Issue Number	4
Journal	American journal of physiology. Regulatory, integrative and comparative physiology
Language	English
Access Restriction	Open
Subject Keyword	Aortic Aneurysm, Thoracic Aortic coarctation Blood Vessel Buffers Calcium Channel Diameter (qualifier value) Dissecting aneurysm of the thoracic aorta Hypertensive disease L-Type Calcium Channels Protein Kinase C Protein Kinases Staphylococcal Protein A torr
Content Type	Text
Resource Type	Article