Chub N L
Neirofiziologiia. 1991;23(3):338-43.
Effect of bath application of L-DOPA, dopamine (DA), noradrenaline (NA) on the spontaneous activity--cyclical oscillations of electrotonic potentials in dorsal and ventral roots (DR and VR, respectively) generated by isolated spinal cord of 16-20-day-old chick embryo was studied. L-DOPA in low concentration (30-150 mumol/l) activated spinal generator: suprathreshold rhythms appeared (i.e., spike activity in DR and VR). High concentration (200-1000 mumol/l) of L-DOPA depressed generator activity, but in the course of washing of the spinal cord spontaneous activity was enhanced and suprathreshold rhythms appeared. DA and NA (50 mumol/l) did not influence the activity but in concentration 100 mumol/l they depressed spontaneous activity in DR and VR. Bath application of 2-amino-5-phosphonovaleric acid (20 mumol/l) blocked activity induced by small concentration of L-DOPA. Activity generated by the neuronal network of the isolated dorsal horn was intensified after bath-application of L-DOPA in small concentration. Rhythmic activity in the isolated ventral horn did not appear after bath-application of L-DOPA. It is concluded that excitatory action of L-DOPA on the neuronal network of dorsal horn chick embryo was direct (i.e., did not depend on catecholamines).
研究了在浴槽中应用左旋多巴（L-DOPA）、多巴胺（DA）、去甲肾上腺素（NA）对16 - 20日龄鸡胚离体脊髓产生的背根和腹根（分别为DR和VR）电紧张电位的自发活动——周期性振荡的影响。低浓度（30 - 150 μmol/L）的L-DOPA激活脊髓发生器：出现阈上节律（即DR和VR中的锋电位活动）。高浓度（200 - 1000 μmol/L）的L-DOPA抑制发生器活动，但在冲洗脊髓的过程中自发活动增强且出现阈上节律。DA和NA（50 μmol/L）不影响活动，但浓度为100 μmol/L时它们抑制DR和VR中的自发活动。浴槽中应用2 - 氨基 - 5 - 磷酸戊酸（20 μmol/L）可阻断低浓度L-DOPA诱导的活动。低浓度L-DOPA浴槽应用后，离体背角神经元网络产生的活动增强。浴槽应用L-DOPA后，离体腹角未出现节律性活动。得出结论：L-DOPA对鸡胚背角神经元网络的兴奋作用是直接的（即不依赖于儿茶酚胺）。
