Evans P D
J Physiol. 1984 Mar;348:325-40. doi: 10.1113/jphysiol.1984.sp015113.
The role of cyclic AMP and calcium in the mediation of the effects of octopamine has been investigated in the extensor tibiae muscle of the hind leg of the locust. Elevation of cyclic AMP levels in the preparation by means of the phosphodiesterase inhibitor, 3-isobutyl-1-methylxanthine (IBMX), by means of the diterpene adenylate cyclase activator, forskolin, and by means of cyclic nucleotide analogues mimics the post-synaptic effects of octopamine application at different frequencies of neuronal stimulation. These conditions also mimic the presynaptic effects of octopamine on spontaneous release of transmitter from the slow motoneurone. The effects of octopamine on the preparation are calcium sensitive, with the maximal sensitivity occurring between 0.5 and 4.0 mM-external calcium. The results are discussed in terms of the role of cyclic AMP and calcium in the mediation of the effects of octopamine.
环磷酸腺苷(cAMP)和钙在介导章鱼胺作用中的角色,已在蝗虫后腿胫节伸肌中进行了研究。通过磷酸二酯酶抑制剂3-异丁基-1-甲基黄嘌呤(IBMX)、二萜腺苷酸环化酶激活剂福斯可林以及环核苷酸类似物,提高标本中的cAMP水平,可模拟在不同神经元刺激频率下施加章鱼胺的突触后效应。这些条件还模拟了章鱼胺对慢运动神经元递质自发释放的突触前效应。章鱼胺对标本的作用对钙敏感,最大敏感性出现在细胞外钙浓度为0.5至4.0 mM之间。本文根据cAMP和钙在介导章鱼胺作用中的角色对结果进行了讨论。