摘要
目的:探讨原发性高血压患者血压参数与血管平滑肌细胞钙激活钾通道(KCa)活性的相关性。方法:切取21例原发性高血压患者(高血压组)及18例非高血压者(血压正常组)的肠系膜动脉小分支节段,用酶消化法获取血管平滑肌细胞,以膜片钳技术检测KCa通道的活性,通过Pclamp专用软件实时采样记录其平均开放时间(To),平均关闭时间(Tc),平均开放概率(Po)等。采用美国Meditech公司的ABPM-04动态血压监护仪,记录24h平均收缩压、24h平均舒张压、24h平均脉压、白昼血压、夜间血压、脉压变异性。结果:①两组血压参数:高血压组24h平均收缩压与平均舒张压、白昼平均收缩压与平均舒张压、夜间平均收缩压与平均舒张压、24h平均脉压、脉压变异性均显著高于血压正常组;②两组KCa通道活性变化:两组于细胞内面向外膜片下,不同浓度Ca2+较Ca2+浓度为0时Po、To增加,Tc缩短,有显著性差异;③高血压组血管平滑肌KCa活性与血压参数的相关性:24h平均舒张压、白昼及夜间平均舒张压、24h平均脉压升高时,Po显著增加,To显著延长,Tc显著缩短。但24h平均收缩压、白昼及夜间平均收缩压、脉压变异性变化与Po、To、Tc关系不明显。结论:原发性高血压患者肠系膜动脉平滑肌KCa通道活性明显高于非高血压者,但对Ca2+的敏感性降低。原发性高血压患者舒张压、
Objective:To study the relationship of parameters of blood pressure and calcium-activated potassium channels( KCa)of vessel smooth muscle cells (SMCs) in patients with essential hypertension (EH). Methods :(1)Vessel SMCs from mesenteric artery branch of 21 EH and 18 normotensive patients were obtained by enzyme digestion. Patch clamp technique was used to study activity of KCa on vessel SMCs. The signal channel open probability ( Po) ,open dwell-time (To) and close dwell- time(Tc) ,open channel number per patch were recorded. (2)24-hour mean sysytolic pressure(SBP), 24-hour mean dilated pressure(DBF) , mean SBP and DBP during daytime and nighttime,mean pulse pressure(PP)and pulse pressure variability (PPV)in EH patients were recorded by ambulatory blood pressure monitoring(ABPM-04 MEDITECH, USA). Results: (1)Compared with normotensive patients , the activities of KCa channels in EH patients was higher. After Ca2+ was added to cytoplasm, Po of KCa channels in normotensive patients was significantly increased. But no change was noted in EH group. (2) We found that when DBP and PP were increased, Po was increased and Tc was shortened, but SBP and PPV showed no significant correlation with Po ,To and Tc. Conclusion: KCa channels had an obvious increased activaty and a decreased sensitive to Ca2+ in patients with EH. The changes of DBP and PP were closely related to KCa channels in patients with EH.
出处
《中国循环杂志》
CSCD
北大核心
2005年第2期126-129,共4页
Chinese Circulation Journal
基金
卫生部默沙东基金资助项目(1997)四川省教育厅自然科学基金重点资助项目(1996-16)
