Hall S, Pennefather J N
Department of Pharmacology, Monash University, Clayton, Victoria, Australia.
Eur J Pharmacol. 1990 Aug 2;184(1):33-42. doi: 10.1016/0014-2999(90)90664-r.
Responses to forskolin and isoprenaline of electrically stimulated preparations of longitudinal and circular myometrium were compared. The guinea-pigs used were: untreated (dioestrous), ovarian steroid-treated, pregnant and post-partum. Forskolin inhibited electrically evoked contractions of both myometrial layers obtained from all groups; there was no change in its potency or its maximum effect (90-100% inhibition). The inhibition of contractions of longitudinal myometrium by isoprenaline was enhanced with steroid treatment, attaining a maximum in late pregnancy and immediately post-partum. In circular myometrium, there was no significant change in the potency of isoprenaline on tissues from ovarian steroid-treated animals. However, maximum potency as well as maximum response was observed in late pregnancy. Since the effects of isoprenaline but not of forskolin were modulated, we suggest that ovarian steroids and pregnancy may alter the coupling of beta-adrenoceptors to the adenylate cyclase system.
比较了电刺激的子宫纵肌层和环肌层制剂对福斯高林和异丙肾上腺素的反应。所用豚鼠分为：未处理（动情间期）、接受卵巢类固醇处理、怀孕和产后。福斯高林抑制了所有组子宫肌层两层的电诱发收缩；其效力或最大效应（90 - 100%抑制）没有变化。类固醇处理增强了异丙肾上腺素对纵肌层收缩的抑制作用，在妊娠晚期和产后立即达到最大抑制效果。在环肌层，异丙肾上腺素对接受卵巢类固醇处理动物的组织的效力没有显著变化。然而，在妊娠晚期观察到了最大效力以及最大反应。由于异丙肾上腺素而非福斯高林的作用受到调节，我们认为卵巢类固醇和妊娠可能会改变β - 肾上腺素能受体与腺苷酸环化酶系统的偶联。
