β-苯基乳酸对离体小鼠子宫的平滑肌作用

EFFECTS OF β-PHENYL LACTIC ACID ON ISOLATED MOUSE UTERUS SMOOTH MUSCLES

(士)β-苯基乳酸(PLA)为合成的丹参素类似物,它能抑制离体小鼠子宫平滑肌的自发收缩,以及雌激素预处理和早孕小鼠的离体子宫平滑肌的张力降低,其作用呈莉量依赖性。其子宫平滑肌的抑制作用与Ca^(2+)、垂体后叶素无关。普萘洛尔能使PLA的剂量一松弛效应曲线右移,最大效应降低,且[~3H]DHA与大鼠肺细胞膜的结合试验表明PLA对该试验无抑制作用,说明PLA的子宫平滑肌的抑制作用与β肾上腺素受体无关。u-46619的PD_2值不受PLA的影响,但PLA的剂量一松弛效应曲线可被u-46519压低,说明其抑制作用与血栓素A_2(TXA_2)的减少有关。

Spotaneous motility of isolated mouse uterine muscles preparations or depolarized isolated mouse uterine smooth, muscles under 2 difference hormonal states (estrogen primed and early pregnancy) were used to test the effect of β-phenyl lactic acid (PLA).The muscle tensions of these prepartions were inhibited by PLA, and there was no relationship between PLA effects and calcium ion or posterior pituitary hormone.Propranolol caused the PLA relaxant dose response curve to shift to the right in a decrease of the maxium response. PLA did not affect the binding of [3H] DHA and rat lung membrane. These results indicate that the inhibitory effects of PLA is not related to the /8-adrenergio receptor.PD2 values of u-16619 was similar to that of u-46619 in the presence of PLA, however, the PLA relaxant dose response shifted to the right in the presence of u-46619. It is suggested that the inhibitory effect of PLA on isolated mouse uterine smooth muscles may be related to decreased amounts of TXA2.