戊巴比妥钠对豚鼠乳头肌电活动和机械活动的影响。
Effects of sodium pentobarbital on electric and mechanical activities of guinea pig papillary muscle.
作者信息
Zhang Y, Gu S Z, Hao Y C, Song L L, Guo S M, Lu S G
机构信息
Department of Physiology, Hebei Medical University, Shijiazhuang, China.
出版信息
Zhongguo Yao Li Xue Bao. 1996 Sep;17(5):439-41.
AIM
To study the effects of sodium pentobarbital (SP) on the action potential (AP) and contraction of guinea pig papillary muscle.
METHODS
Using conventional glass microelectrode and mechanical recording of myocardium contraction.
RESULTS
SP (> or = 10 mumol.L-1) prolonged the AP duration (APD) and effective refractory period (ERP), while amplitude (APA) and Vmax of phase 0 showed no changes. The effects of SP were abolished by pretreatment with cromakalim, an agonist of ATP-sensitive K+ channel. The maximal isometric tension (Pmax) and velocity of tension development (dT/dt) were decreased to 51% and 48% of control, respectively. The first postrest beat (B1) and second postrest beat (B2) were also depressed.
CONCLUSION
SP affected the action potential by reducing activities of the K+ channels and reduced the contraction of guinea pig myocardium.
目的
研究戊巴比妥钠（SP）对豚鼠乳头肌动作电位（AP）及收缩的影响。
方法
采用常规玻璃微电极并进行心肌收缩的机械记录。
结果
SP（≥10μmol·L-1）可延长动作电位时程（APD）和有效不应期（ERP），而0期振幅（APA）和最大除极速度（Vmax）无变化。ATP敏感性钾通道激动剂克罗卡林预处理可消除SP的作用。最大等长张力（Pmax）和张力发展速度（dT/dt）分别降至对照的51%和48%。静息后第一个搏动（B1）和第二个搏动（B2）也受到抑制。
结论
SP通过降低钾通道活性影响动作电位，并降低豚鼠心肌收缩力。
Zotero 插件