Lg. Malloy et Md. Sauro, TYROSINE KINASE INHIBITION SUPPRESSES ANGIOTENSIN CONTRACTION IN HYPERTENSIVE AND NORMOTENSIVE SMALL RESISTANCE ARTERIES, Life sciences, 58(19), 1996, pp. 317-324
Citations number
20
Categorie Soggetti
Biology,"Medicine, Research & Experimental","Pharmacology & Pharmacy
Protein tyrosine kinases (PTKs) may influence vascular resistance, whi
ch is controlled primarily at the level of small arteries and arteriol
es. This study evaluates these kinases in resistance arteries from spo
ntaneously hypertensive (SHR) and normotensive (WKY) rats using the pr
otein tyrosine kinase inhibitor, tyrphostin-25. Gracilis muscle arteri
es (90-160 um, internal diameter) were mounted on a resistance vessel
myograph and contractile responses to phenylephrine (PE) and angiotens
in II (AII) were measured in the presence and absence of tyrphostin-25
(0.02-20 uM). Tyrphostin-25 inhibited AII, but not PE contractions an
d was less potent in the hypertensive arteries. This demonstrates for
the first time that PTKs contribute to the contractile activity of res
istance arteries from both hypertensive and normotensive rats. Further
, results confirm in small arteries that AII-induced contractions are
PTK-dependent and that arteries from hypertensive rats are hyporespons
ive to PTK inhibition.