Open AccessContractile Responses and Myosin Phosphorylation in Reconstituted Fibers of Smooth Muscle Cells From the Rat Cerebral Artery
Author(s) -
Kazuhiko Oishi,
Yoshitaka Takatoh,
Jianjun Bao,
Masaatsu K. Uchida
Publication year - 2002
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - English
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.90.36
Subject(s) - myosin light chain kinase , contraction (grammar) , myosin , protein kinase c , chemistry , rho associated protein kinase , medicine , biophysics , staurosporine , endocrinology , rho kinase inhibitor , channel blocker , calmodulin , dids , phosphorylation , biochemistry , biology , calcium , membrane
String-shaped reconstituted smooth muscle fibers were prepared in rectangular wells by thermal gelation of a mixed solution of collagen and cultured smooth muscle cells derived from the rat cerebral artery. The fibers contracted in response to KCl, 5-hydroxytryptamine (5-HT), noradrenaline, endothelin-1, endothelin-2, angiotensin II, prostaglandin F2alpha and prostaglandin E2. 5-HT-induced contraction was partially inhibited by the L-type voltage-dependent Ca2+ channel inhibitor nifedipine, putative non-selective cationic channel inhibitor SKF96365 and intracellular Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTA-AM), and completely abolished by the myosin light chain kinase inhibitor ML-9. The fibers pre-contracted by 5-HT were completely relaxed by the Rho kinase inhibitor Y-27632, serine/threonine kinase inhibitor staurosporine, 8-bromo cyclic GMP and papaverine, and partially relaxed by dibutyryl cyclic AMP. Moreover, 5-HT as well as endothelin-1 and KCl enhanced 20-kDa myosin light chain phosphorylation in the fibers. These results suggested that the characteristics of contraction of the fibers reflect typical contractilities of vascular smooth muscle tissues. This technique will allow us to directly address questions relating to heterogeneity of receptor mechanisms and intracellular pathways of vascular smooth muscle contraction as a function of vessel type.