子宫环形肌和纵形肌对去甲肾上腺素的敏感性。

Sensitivity of circular and longitudinal uterine muscles to noradrenaline.

作者信息

Chernaeva L, Milenov K

出版信息

Methods Find Exp Clin Pharmacol. 1982;4(2):89-97.

Abstract

Spontaneous contractions of circular and longitudinal uterine muscles of rat and rabbit during estrogen domination were recorded in vitro isometrically. The circular muscles of both uteri contracted more frequently than the longitudinal muscles. Noradrenaline inhibited the spontaneous contractions of the longitudinal (ED50 = 5x10(-7) M) and circular (ED50 = 4.9x10(-6) M) rat uterine muscles. One molecule of noradrenaline bound 0.35 receptors in the circular and 0.63 receptors in the longitudinal rat muscles. Noradrenaline increased both amplitude and frequency of the rabbit uterine contractions (ED50 = 5.8x10(-9) M for the circular and 1x10(-7) M for the longitudinal muscles). One molecule of noradrenaline bound 0.63 receptors in the circular and 0.84 receptors in the longitudinal muscle of the rabbit uterus. The response of the longitudinal rabbit muscle to noradrenaline was influenced by D-600 to a larger degree than that of the circular muscle. The different sensitivity to noradrenaline of the circular and longitudinal uterine muscles may be explained by the different number of adrenoceptors and their binding sites as well as by some differences in calcium utilization.

摘要

在雌激素占主导期间，对大鼠和家兔子宫的环形肌和纵形肌的自发性收缩进行了体外等长记录。两种子宫的环形肌收缩频率均高于纵形肌。去甲肾上腺素抑制大鼠子宫纵形肌（ED50 = 5×10⁻⁷ M）和环形肌（ED50 = 4.9×10⁻⁶ M）的自发性收缩。一个去甲肾上腺素分子在大鼠环形肌中结合0.35个受体，在纵形肌中结合0.63个受体。去甲肾上腺素增加家兔子宫收缩的幅度和频率（环形肌的ED50 = 5.8×10⁻⁹ M，纵形肌的ED50 = 1×10⁻⁷ M）。一个去甲肾上腺素分子在家兔子宫环形肌中结合0.63个受体，在纵形肌中结合0.84个受体。家兔纵形肌对去甲肾上腺素的反应受D - 600的影响程度大于环形肌。子宫环形肌和纵形肌对去甲肾上腺素的不同敏感性可能由肾上腺素能受体及其结合位点的数量差异以及钙利用的一些差异来解释。