Zhang Y, Hao Y C, Song L L, Guo S M, Gu S Z, Lu S G
Department of Physiology, Hebei Medical University, Shijiazhuang, China.
Zhongguo Yao Li Xue Bao. 1998 May;19(3):248-50.
To study the effects of sex hormones, estradiol (Est), progesterone (Pro) and testosterone (Tes) on the action potential (AP) and contraction of guinea pig papillary muscle.
Using conventional glass microelectrode and mechanical recording of myocardial contraction.
Est slowed down the maximal rate of rise of phase 0 (Vmax) of AP at low concentration (1 mumol.L-1). At 10 mumol.L-1 and above, Est also prolonged AP duration (APD50 and APD90), effective refractory period (ERP) and decreased the maximal isometric tension (Pmax) and velocity of tension development (dT/dt) of contraction. Tes (100 mumol.L-1 - 1 mmol.L-1) prolonged APD90 and ERP with decreased Pmax and dT/dt. But Pro (1 mumol.L-1 - 1 mmol.L-1) had no effects on both AP and contraction.
Est prolonged AP and depressed contraction of guinea pig papillary muscle.
研究性激素雌二醇(Est)、孕酮(Pro)和睾酮(Tes)对豚鼠乳头肌动作电位(AP)及收缩的影响。
采用传统玻璃微电极并机械记录心肌收缩。
低浓度(1μmol·L-1)时,Est使AP的0期最大上升速率(Vmax)减慢。在10μmol·L-1及以上时,Est还可延长AP时程(APD50和APD90)、有效不应期(ERP),并降低收缩的最大等长张力(Pmax)和张力发展速度(dT/dt)。Tes(100μmol·L-1 - 1mmol·L-1)可延长APD90和ERP,同时降低Pmax和dT/dt。但Pro(1μmol·L-1 - 1mmol·L-1)对AP和收缩均无影响。
Est可延长豚鼠乳头肌AP并抑制其收缩。