C-TYPE NATRIURETIC PEPTIDE INHIBITS UPR EGULATION OF α1-ADRENOCEPTOR AND INOSITO L 1,4,5-TRISPHOSPHATE RECEPTOR IN RAT VASCULAR SMOOTH MUSCLE AFTER VASCULAR ENDOTHELIAL INJURY

摘要

Objective.In a model of balloon injury of rat aortic endothelium, the effects of C-type natriuretic peptide(CNP) on α 1-adrenoreceptor and inositol 1,4,5-triphosphate (IP 3) receptor were studied Methods. Aortic injuries were produced by vascular endothelium-denudation.α 1- adrenoreceptor in smooth muscle sarcolemma and IP 3 receptor in smooth muscle sarcoplasmic reticulum in the rat aorta were assayed by radioactive analysis method Results. It was found that neointima was formed and the contents of DNA, collagen and elastin of each intimamedia were significantly increased in 7 days and 21 days after balloon injury of rat aorta. α 1adrenoreceptor in smooth muscle sarcolemma and IP 3 receptor in sarcoplasmic reticulum were also upregulated. Results also showed that the administration of CNP ip significantly decreased the contents of DNA, collagen and elastin of each intimamedia, and inhibited the upregulation of α 1adrenoreceptor and IP 3 receptor Conclusion. The inhibition of the upregulation of α 1adrenoreceptor and IP 3 receptor by CNP might be one of the mechanisms of its suppressive action on intimal