Effect of neurotensin on mechanical and intracellular electrical activity of the canine stomach.
Effect of neurotensin on mechanical and intracellular electrical activity of the canine stomach.
复制标题
神经降压素对犬胃机械和细胞内电活动的影响。
DOI：
10.1152/ajpgi.1982.243.5.g404
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发表时间：
1982
期刊：
影响因子：
--
通讯作者：
Szurszewski,JH
中科院分区：
文献类型：
--
作者：
Sanders,KM;Schmalz,P;Szurszewski,JH
采用细胞内微电极和标准器官浴技术，体外研究了神经紧张素对犬心房圆形平滑肌电和机械活动的影响。神经紧张素减少或消除自发收缩。毒蕈碱、肾上腺素能拮抗剂和河豚毒素不能阻断神经紧张素的作用，提示神经紧张素的作用是直接作用于平滑肌细胞。虽然去甲肾上腺素和神经紧张素的抑制作用相似，但神经紧张素的作用似乎不是通过肾上腺素能机制发生的，因为α和β受体阻断没有作用。神经紧张素还能减少或消除五宫泌素和乙酰胆碱引起的收缩。神经紧张素对自发性乙酰胆碱和戊胃泌素刺激的收缩的抑制作用与胃动作电位平台电位的振幅和持续时间的减少有关。数据表明，神经紧张素对心房收缩的调节是通过一种电压依赖性机制发生的，这种机制在平台电位期间起作用。
Intracellular microelectrode and standard organ bath techniques were used to study in vitro the effects of neurotensin on the electrical and mechanical activities of canine antral circular smooth muscle. Neurotensin reduced or abolished spontaneous contractions. Muscarinic and adrenergic antagonists and tetrodotoxin did not block the effects of neurotensin, suggesting that the action of neurotensin was due to a direct action on the smooth muscle cell. Although the inhibitory effect of norepinephrine and neurotensin was similar, the effect of neurotensin did not appear to occur by an adrenergic mechanism because alpha- and beta-receptor blockade had no effect. Neurotensin also reduced or abolished contractions stimulated by pentagastrin and acetylcholine. The inhibitory effect of neurotensin on spontaneous acetylcholine- and pentagastrin-stimulated contractions was associated with a decrease in the amplitude and duration of the plateau potential of the gastric action potential. The data suggest that modulation of antral contractions by neurotensin occurs through a voltage-dependent mechanism that operates during the plateau potential.