Maximal rates of activation in electrically stimulated swine carotid media.
Maximal rates of activation in electrically stimulated swine carotid media.
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电刺激猪颈动脉中层的最大激活率。
DOI：
10.1161/01.res.60.3.438
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发表时间：
1987
影响因子：
20.1
通讯作者：
Murphy,RA
中科院分区：
文献类型：
--
作者：
Singer,HA;Murphy,RA
动脉平滑肌中的跨桥磷酸化和细胞活化速率的动力学是未知的，并且响应速率通常受到激动剂扩散速率的限制。在这项研究中，电场刺激（10-20 V AC，60 Hz）用于激活猪颈动脉平滑肌条。用0.5 μ M酚苄明（PBZ）预处理30分钟可显著抑制肾上腺素能神经释放去甲肾上腺素引起的场刺激应激。添加1-10 mM四乙基铵离子（TEA）PBZ预处理的组织允许直接刺激的肌肉细胞，并显着增强了现场刺激的反应。用PBZ和TEA预处理的场刺激组织中的激活被Ca 2+通道拮抗剂维拉帕米（0.5 μ M，15分钟）强烈抑制。激活迅速，肌球蛋白轻链（MLC）磷酸化值上升到总MLC的50%以上，半衰期约为1秒。应力和僵硬的发展是双相的，第一阶段的估计半衰期为3秒。在刺激5秒后，应力和刚度继续缓慢上升，而MLC磷酸化在5秒和10秒之间显著下降至35-40%的几乎恒定值，持续长达60秒。卸载缩短速度是最大的（0.067 Lo/sec）在最早的时间点检查（0.5秒），之前显着的压力发展和次最大磷酸化。10秒后观察到无负荷缩短速度显著降低。这些结果表明，磷酸化和去磷酸化的动力学和激活率在这个动脉平滑肌中是非常快的。
The kinetics of crossbridge phosphorylation and cellular activation rates in arterial smooth muscle are unknown, and the response rates are usually limited by agonist diffusion rates. In this study, electrical field stimulation (10-20 V AC, 60 Hz) was used to activate strips of swine carotid artery smooth muscle. Pretreatment with 0.5 microM phenoxybenzamine (PBZ) for 30 minutes significantly inhibited field stimulated stress due to norepinephrine released from adrenergic nerves. Addition of 1-10 mM tetraethylammonium ion (TEA) to PBZ-pretreated tissues allowed direct stimulation of muscle cells and significantly potentiated the response to field stimulation. Activation in field stimulated tissues pretreated with PBZ and TEA was strongly inhibited by the Ca2+-channel antagonist verapamil (0.5 microM for 15 minutes). Activation was rapid with myosin light chain (MLC)-phosphorylation values rising to greater than 50% of total MLC, with a half-time of approximately 1 second. Stress and stiffness development was biphasic and lagged with an estimated half-time for the first phase of 3 seconds. Stress and stiffness continued to slowly rise after 5 seconds of stimulation, while MLC phosphorylation declined significantly between 5 and 10 seconds to a nearly constant value of 35-40% for up to 60 seconds. Unloaded shortening velocity was maximal (0.067 Lo/sec) at the earliest time point examined (0.5 second), prior to significant stress development and at submaximal phosphorylation. Significant decreases in unloaded shortening velocity were observed after 10 seconds. These results show that the kinetics of phosphorylation and dephosphorylation and the rates of activation are very rapid in this arterial smooth muscle.
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四乙铵增强血管反应的机制：一种新型的致敏形式。
影响因子：
2.1
作者：
S. Kalsner
通讯作者：
S. Kalsner
DOI：
10.1152/ajpcell.1984.246.5.c510
发表时间：
1984
期刊：
The American journal of physiology
影响因子：
--
作者：
Krisanda,JM;Paul,RJ
通讯作者：
Paul,RJ
影响因子：
7.8
作者：
Kannan, M S;Daniel, E E
通讯作者：
Daniel, E E
四乙铵诱导的犬气管平滑肌节律性收缩的特征：钠泵抑制作用。
影响因子：
2.1
作者：
M. Watanabe;Y. Imaizumi;Y. Kasuya
通讯作者：
Y. Kasuya
去甲肾上腺素诱导的血管平滑肌去极化与收缩之间的关系。
DOI：
10.1159/000158152
发表时间：
1978
期刊：
Blood vessels
影响因子：
--
作者：
G. Haeusler
通讯作者：
G. Haeusler