【摘要】 ET,Car和Oxy使在高钾液中的雌激素处理和早、中、晚孕的小鼠子宫产生浓度依赖性张力增加,ET对晚孕子宫的 E_max是早孕者的1.33倍,Car对中孕子宫的 E_max为晚孕者的2倍,Oxy对晚孕子宫的E_max是中孕者的3.2倍。ET对不同孕期子宫的EC₅₀无显著差别,是Car的2％—7％,为Oxy的3—15倍。表明ET对小鼠子宫的兴奋作用不同于Car和Oxy。更多还原

【Abstract】 Mouse uterine horns from 4 states (estrogen-primed and early-, mid-, and late-pregnancy ) were used to study the effect of endothelin-1 (ET) vs carboprost (Car) and oxytocin (Oxy). In K±-Krebs (KC1 40 mmol ·L-1) solution, ET (1-300 nmol·L-1), Car (0. 002 - 20μmol·L-1), and Oxy (0.6 - 60 nmol·L-1) evoked concentration-dependent increases in tension of the uterine horns from 4 different states. Emrx for ET were 1.12± 0. 26, 1. 27 ± 0. 18, and 1. 49 ± 0. 13 g in early-, mid-, and late-pregnancies, respectively. Emax for Car in mid- was twice, that in late-pregnancy , whereas Emax for Oxy in late- was thrice that in mid-pregnancy. EC50 for ET were 9.6, 5.8, and 6.3 nmol·L-1 in early-, mid-, and late-pregnancies, respectively, and were only 2 % to 7 % of that for Car and 3 -15 times of that for Oxy in various gravid stages. The results suggest that the contractile activity of pregnant mouse uterus to ET is more potent than that of Car while slightly weaker than that of Oxy.更多还原