摘要
目的探讨失血性休克对大鼠肠系膜上动脉血管平滑肌BKCa通道酪氨酸磷酸化的影响以及NO对BKCa通道酪氨酸磷酸化的调控。方法建立大鼠失血性休克模型[(35±5)mmHg]并提取肠系膜上动脉总裂解蛋白,采用免疫沉淀及免疫印迹技术,观察休克血管平滑肌BKCa通道酪氨酸磷酸化的变化情况;采用原代培养的大鼠肠系膜上动脉血管平滑肌细胞,观察NO对BKCa通道酪氨酸磷酸化的调控及其时-效、量-效关系。结果失血性休克2h及4h后大鼠肠系膜上动脉血管平滑肌BKCa通道α亚基酪氨酸磷酸化明显增强(P<001);L-精氨酸(5×10-5-5×10-4mol/L)孵育30min即可诱导培养血管平滑肌细胞BKCa通道α亚基酪氨酸磷酸化增强,2h内无明显下降;且L-精氨酸诱导BKCa通道α亚基酪氨酸磷酸化具有剂量依赖性。结论重症失血性休克可增强血管平滑肌BKCa通道酪氨酸磷酸化,且NO参与了该调控过程。
AIM: To study the effects of hemorrhagic shock on BK Ca channel tyrosine phosphorylation in rat superior mesenteric artery and the role of nitric oxide (NO) in BK Ca channel tyrosine phosphorylation. METHODS: The hemorrhagic shock model [(35±5) mmHg] was established in rats and the whole lysate of superior mesenteric artery were extracted and analyzed by immune precipition (IP) and immunoblotting. The tyrosine phosphorylation levels of BK Ca channel alpha-subunit in mesenteric artery in hemorrhagic shock rats were investigated, and the modulation of BK Ca channel alpha-subunit tyrosine phosphorylation by NO and its dose-and time-dependended relationships were observed. RESULTS: The tyrosine phosphorylation level of BK Ca channel alpha-subunit in mesenteric artery in rats increased significantly after hemorrhagic shock 2 h and 4 h (P<0.01 ), and L-arginine (5×10 -5 -5×10 -4 mol/L) up-regulated BK Ca channel alpha-subunit tyrosine phosphorylation in primary cultured VSMC in a 30 min incubation and without significant decrease after 2 h; L-arginine induced BK Ca channel alpha-subunit tyrosine phosphorylation in a dose-dependent manner. CONCLUSION: Hemorrhagic shock enhances BK Ca channel tyrosine phosphorylation in resistant artery in rats, and NO is involved in this process. [
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2004年第12期2189-2193,共5页
Chinese Journal of Pathophysiology
基金
973资助项目(No.G1999054202)
