Cruz-Bermúdez Nelson D, Marder Eve
Volen Center for Complex Systems and Department of Biology, Brandeis University, MS-013, 415 South Street, Waltham, MA 02454, USA.
J Exp Biol. 2007 Aug;210(Pt 16):2873-84. doi: 10.1242/jeb.002949.
Neuromodulators can change the output of neural circuits. The crustacean cardiac ganglion (CG) drives the contractions of the heart. The CG is a direct target for neurohormones that are released from the pericardial organs and other neuroendocrine sites. In this study, we have characterized for the first time the physiological actions of the peptides red pigment concentrating hormone (RPCH), Cancer borealis tachykinin-related peptide Ia (CabTRP Ia) and allatostatin III type A (AST-3) on the isolated CG of the crab, Cancer borealis. RPCH and CabTRP Ia excited the CG while AST-3 strongly inhibited its motor output. We also studied the actions of other peptides and small molecule transmitters known to be present in C. borealis. Dopamine, serotonin, proctolin, crustacean cardioactive peptide (CCAP), a number of extended FLRFamide peptides, and cholinergic agonists increased the activity of the CG, GABA inhibited the CG, while other substances had little or no significant effect on the CG motor pattern. These results demonstrate, in one species, that the CG is multiply modulated. We suggest that multiple modulators may be important to regulate and coordinate the activity of the heart and other organs in response to external stimuli or the endogenous physiological state.
神经调质可以改变神经回路的输出。甲壳类动物的心脏神经节（CG）驱动心脏的收缩。CG是来自心包器官和其他神经内分泌部位释放的神经激素的直接作用靶点。在本研究中，我们首次对红色素浓缩激素（RPCH）、北方黄道蟹速激肽相关肽Ia（CabTRP Ia）和抑咽侧体素III A型（AST-3）这几种肽对北方黄道蟹分离出的CG的生理作用进行了表征。RPCH和CabTRP Ia使CG兴奋，而AST-3强烈抑制其运动输出。我们还研究了已知存在于北方黄道蟹中的其他肽和小分子递质的作用。多巴胺、5-羟色胺、促肠肌肽、甲壳类动物心脏活性肽（CCAP）、一些延长型FLRFamide肽和胆碱能激动剂增加了CG的活性，γ-氨基丁酸抑制CG，而其他物质对CG的运动模式几乎没有或没有显著影响。这些结果表明，在一个物种中，CG受到多种调节。我们认为多种调节剂对于响应外部刺激或内源性生理状态来调节和协调心脏及其他器官的活动可能很重要。
