Lloyd P E, Kupfermann I, Weiss K R
Proc Natl Acad Sci U S A. 1984 May;81(9):2934-7. doi: 10.1073/pnas.81.9.2934.
The neuropeptide designated SCPB (small cardioactive peptide B), the sequence of which has recently been determined, was found in the accessory radula closer muscle, a muscle involved in biting movements. The ganglia and nerves that innervate the accessory radula closer muscle also contain SCPB. At nanomolar concentrations, it enhances the contractions of the muscle. The effect of SCPB on the muscle resembles the effect of an identified serotonergic neuron that previously was shown to mediate behavioral effects that reflect a food arousal state in Aplysia. Like serotonin, SCPB enhances contractions by a postsynaptic action, which appears to involve an increase in cAMP levels in the muscle. Our findings suggest that parallel peptidergic and serotonergic pathways may mediate similar aspects of arousal in Aplysia.
名为SCPB（小的心脏活性肽B）的神经肽，其序列最近已被确定，在副齿舌闭合肌中被发现，该肌肉参与咬的动作。支配副齿舌闭合肌的神经节和神经也含有SCPB。在纳摩尔浓度下，它增强肌肉的收缩。SCPB对肌肉的作用类似于一种已确定的5-羟色胺能神经元的作用，该神经元先前被证明介导反映海兔食物激发状态的行为效应。与5-羟色胺一样，SCPB通过突触后作用增强收缩，这似乎涉及肌肉中cAMP水平的升高。我们的研究结果表明，平行的肽能和5-羟色胺能途径可能介导海兔激发的相似方面。
