Klaassen L W, Kammer A E, Fitch G K
J Neurobiol. 1986 Jul;17(4):291-302. doi: 10.1002/neu.480170404.
Intracellular recordings of excitatory junction potentials (EJPs) and miniature EJPs (MEJPs) were made from the dorsal longitudinal muscle of Manduca sexta to determine the sites of action of octopamine. MEJPs increased in amplitude and frequency as the moth developed during the 3 days before eclosion. DL-Octopamine (5 X 10(-6) M) increased the amplitude of excitatory junction potentials in both immature moths (one day before eclosion) and adults. Octopamine (10(-5) M) also increased the amplitude and frequency of MEJPs from immature animals (one and two days before eclosion) but had the opposite effect on adults and pharate adults ready to eclose. Treatment with octopamine (10(-5) M) resulted in a decrease in input resistance and a hyperpolarization in both immature and adult muscle fibers. The results suggest that octopamine acts both presynaptically and postsynaptically but that the increase in the amplitude of the evoked response is due primarily to influences on presynaptic processes.
为了确定章鱼胺的作用位点，对烟草天蛾的背纵肌进行了兴奋性突触后电位（EJP）和微小兴奋性突触后电位（MEJP）的细胞内记录。在羽化前3天，随着蛾的发育，MEJP的幅度和频率增加。DL-章鱼胺（5×10⁻⁶ M）增加了未成熟蛾（羽化前一天）和成虫的兴奋性突触后电位的幅度。章鱼胺（10⁻⁵ M）也增加了未成熟动物（羽化前一天和两天）的MEJP的幅度和频率，但对成虫和即将羽化的蛹期成虫有相反的作用。用章鱼胺（10⁻⁵ M）处理导致未成熟和成熟肌纤维的输入电阻降低和超极化。结果表明，章鱼胺在突触前和突触后都有作用，但诱发反应幅度的增加主要是由于对突触前过程的影响。
