Decreased myogenic reactivity in skeletal muscle arterioles after hypothermic cardiopulmonary bypass
Decreased myogenic reactivity in skeletal muscle arterioles after hypothermic cardiopulmonary bypass
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DOI：
10.1006/jsre.1997.5020
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发表时间：
1997-04-01
影响因子：
2.2
通讯作者：
Sellke, FW
中科院分区：
文献类型：
--
作者：
Wang, SY;Stamler, A;Sellke, FW
体外循环（CPB）与血管平滑肌内在控制的广泛性缺陷有关。为了确定CPB是否改变了骨骼肌小动脉的肌原性反应性，将绵羊（n = 7）置于低温CPB（27℃）上90分钟，心脏用冷水休息。心脏骤停（[K+] = 25 mM） 60分钟。在CPB前（对照组）和CPB后15 min分别从股薄肌分离小动脉（70 ~ 180 μ m）。用视频显微镜观察体外小动脉反应。检查了肌原性反应性，以逐步增加从10到100毫米银的腔内压力。平均动脉压由CPB前的80 +/- 15降至CPB后15分钟的55 +/- 4 mm Hg （P < 0.01）。对照组血管出现肌原性收缩，蛋白激酶C抑制剂staurosporine明显减弱了肌原性收缩（P < 0.01）。CPB降低了肌原性收缩，使压力-直径关系向上移动，表明内在张力降低（与对照组相比P < 0.05）。CPB使α(1)-肾上腺素受体激动剂苯肾上腺素的收缩反应从-43 +/- 7%降至-23 +/- 5% (P < 0.01)，使蛋白激酶C激活剂12-脱氧磷- 13-异丁酸20-乙酸（磷酯）的收缩反应从-64 +/- 6%降至-38 +/- 16% （P < 0.01）。cpb相关的骨骼肌小动脉肌原性反应性降低可能是由于蛋白激酶C和/或下游信号转导的改变。这可能部分解释了CPB相关的全身血管阻力和低血压的降低，(C) 1997学术出版社。
Cardiopulmonary bypass (CPB) is associated with a generalized defect in the intrinsic control of vascular smooth muscle, To determine if myogenic reactivity of skeletal muscle arterioles was altered by CPB, sheep (n = 7) were placed on hypothermic CPB (27 degrees C) for 90 min and hearts were al-rested by cold blood. cardioplegia ([K+] = 25 mM) for 60 min. Arterioles (70-180 mu m) were isolated from the gracilis muscle before (control) and 15 min after CPB. Itt vitro arteriolar responses were studied with video-microscopy. Myogenic reactivity was examined to stepwise increases in intraluminal pressure from 10 to 100 mm Ag. Mean arterial pressure was decreased from 80 +/- 15 prior to CPB to 55 +/- 4 mm Hg (P < 0.01) 15 min after CPB. Myogenic contraction was observed in control vessels and was markedly attenuated by the protein kinase C inhibitor staurosporine (P < 0.01). CPB decreased myogenic contraction and shifted the pressure-diameter relation upward,suggesting a decrease in the intrinsic tone (both P < 0.05 us control). CPB reduced contractile responses to the alpha(1)-adrenoceptor agonist phenylephrine from -43 +/- 7% to -23 +/- 5% (P < 0.01) and the protein kinase C activator 12-deoxyphorbol 13-isobutyrate 20-acetate (phorbol ester) from -64 +/- 6% to -38 +/- 16% (P < 0.01). CPB-associated decrease in myogenic reactivity of skeletal muscle arterioles is Likely due to alterations in protein kinase C and/or downstream signal transduction. This may account in part for reduction in systemic vascular resistance and hypotension associated with CPB, (C) 1997 Academic Press.