血管活性肽对同型半胱氨酸刺激平滑肌细胞增殖的实验研究

目的 观察对兔主动脉平滑肌细胞（ＶＳＭＣ）增殖起负调节作用的Ｃ－型利钠利尿肽（ＣＮＰ）、肾上腺髓质素（Ａｄｍ）、降钙素基因相关肽（ＣＧＲＰ）、生长抑素（ＳＳＴ）和甲状旁腺素相关蛋白（ＰＴＨｒＰ）等活性肽对同型半胱氨酸（Ｈｃｙ）刺激的ＶＳＭＣ增殖的影响。方法 ６只大耳白兔胸主动脉贴块法离体培养平滑肌细胞；分对照及Ｈｃｙ加不同处理因素组；＾３Ｈ－ＴｄＲ掺入测定ＶＳＭＣ增殖；差速离心分离细胞膜、胞浆及胞

Influence of vasoactive peptides on homocysteine-induced proliferation of cultured rabbit vascular smooth muscle cell]

OBJECTIVE: To study the effects of vasoactive peptides adrenomedullin (Adm), C-type natriuretic peptide (CNP), calcitonin gene related peptide (CGRP), somatostatin(SST) and parathyroid hormone-related protein] on homocysteine (Hcy)-induced proliferation of cultured rabbit vascular smooth muscle cell (VSMC). METHODS: Techniques of cell culture, 3H-thymidine incorporation, nuclei, membrane and cytosol fractions were isolated by differential centrifugation and PKC activity was measured. RESULTS: Hcy significantly stimulated DNA synthesis of VSMC. Adm, CNP, CGRP, SST, and PTHrP had no effect on basal 3H-TdR incorporation, but they could inhibit Hcy-induced 3H-TdR incorporation in dose-dependent manner. PKC inhibitor (H7 and Stauroporine) could inhibit VSMC proliferation induced by Hcy with reduction of 3H-TdR incorporation by 50% (P < 0.01) and 56% (P < 0.01), respectively. PKC was found to be distributed equally in nuclear fraction and membrane particulate, and higher in cytosol fraction in untreated VSMC. Treatment of VSMC with 10(-4) mol/L Hcy resulted in a significant increase in membrane-associated PKC combined with a loss of enzyme activity in the cytosol and nuclear fractions. Adm, CNP, CGRP and PTHrP altered the distribution of PKC activity induced by Hcy. CONCLUSION: Adm, CNP, CGRP and PTHrP inhibited VSMC proliferation possibly through PKC pathway.