Neural control of circulation in Aplysia. III. Neurotransmitters.
Neural control of circulation in Aplysia. III. Neurotransmitters.
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海兔循环的神经控制。
DOI：
10.1152/jn.1975.38.4.767
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发表时间：
1975
影响因子：
2.5
通讯作者：
E. Mayeri
中科院分区：
文献类型：
--
作者：
G. Liebeswar;J. Goldman;J. Koester;E. Mayeri
在海兔的腹神经节中，已经描述了七个运动神经元，它们调节肌源性心跳和血管舒缩张力(28)。这些神经元通过化学传递来调节它们的运动效应。在这篇论文中，我们试图指定其中六个运动神经元的传递器。我们研究了几种常见的递质对神经结构的影响，并将这些效应与刺激运动神经元的效应进行了比较，2)考察了阻滞剂是否同样影响了假定的递质对支配结构的影响，以及3)测试了运动神经元从前体合成假定的递质的能力。用低浓度5-羟色胺灌流心脏，模拟兴奋运动神经元Rb(HE)的正性变力和变时性作用。Cinanserin阻断运动神经元兴奋和5-羟色胺灌流的效应。Rb(HE)也被证明能从直接注入细胞体的L-[~3H]色氨酸合成[~H]5-羟色胺。用乙酰胆碱灌流心脏来模拟放电两个LD(HI)心脏抑制运动神经元的效应。苯并喹啉阻断了抑制运动神经元和乙酰胆碱灌流的作用。槟榔碱灌流也抑制了心跳。将乙酰胆碱应用于动脉，可模拟由Lb(Vc)运动神经元引起的血管收缩。六甲溴铵和库拉雷可阻断对Lb(VC)细胞活动或乙酰胆碱反应的主动脉收缩。心脏抑制物和血管收缩运动神经元将[~3H]胆碱注入细胞体，合成[~3H]乙酰胆碱。因此，就像脊椎动物一样，乙酰胆碱对心脏有抑制作用。然而，与脊椎动物不同，5-羟色胺介导心脏兴奋，乙酰胆碱介导外周血管收缩。
In the abdominal ganglion of Aplysia californica, seven motoneurons have been described which modulate the myogenic heart beat and vasomotor tone (28). These neurons mediate their motor effects by chemical transmission. In this paper we have attempted to specify the transmitters of six of these motoneurons. We have 1) studied the effects of several common transmitters on the innervated structures and compared these effects with the effects of firing the motoneurons, 2) examined whether blocking agents influence similarly the effect of a putative transmitter applied to the innervated structure and the effect of firing a motoneuron, and 3) tested the capability of the motoneurons to synthesize the putative transmitters from precursors. The positive inotropic and chronotropic effects of firing the excitor motoneuron RB(HE) were mimicked by perfusion of the heart with serotonin at a low concentration. Cinanserin blocked both the effects of motoneuron excitation and serotonin perfusion. RB(HE) was also shown to synthesize [3H]serotonin from L-[3H]tryptophan injected directly into the cell body. The effects of firing the two LD(HI) heart-inhibitory motoneurons were mimicked by perfusion of the heart with acetylcholine. Benzoquinonium blocked the effects of the inhibitory motoneuron and acetylcholine perfusion. Perfusion with arecoline also inhibited the heart beat. Acetylcholine applied to the arteries mimicked the vasoconstriction caused by the LB(VC) motoneurons. Aortic constriction in response to activity in LB(VC) cells or to acetylcholine was blocked by hexamethonium and curare. The heart inhibitor and vasoconstrictor motoneurons synthesized [3H] acetylcholine from [3H] choline injected into their cell bodies. Thus, as in vertebrates, acetylcholine mediates inhibition to the heart. Unlike vertebrates, however, serotonin mediates excitation to the heart and acetylcholine mediates peripheral vasoconstriction.