Escames G, Acuña Castroviejo D, Vives F
Facultad de Medicina, Departmento de Fisiologia, Universidad de Granada, Spain.
Neuroreport. 1996 Jan 31;7(2):597-600. doi: 10.1097/00001756-199601310-00053.
The excitatory response to motor cortex stimulation of 201 striatal neurones was recorded electrophysiologically to test the effects of melatonin (aMT) and/or D1 and D2 antagonists. Iontophoresis of aMT attenuated the excitatory response in 68.5% of neurones, with a latency of 2-4 min and enhanced the excitatory response in 11.9% of the neurones; 19.6% showed no change in response. Iontophoresis of sulpiride (D2 antagonist) produced an immediate increase in the excitatory response in 62.8% of neurones, an attenuation in 2.3% and no change in the response of 34.9%. The ejection of sulpiride counteracted the aMT-dependent inhibition of the excitatory response of striatal neurones. SCH-23390 (D1 antagonist) iontophoresis had no significant effect. The results show that the same striatal units may be driven by aMT and D2 receptors. However, the significant difference in the latency of the responses suggests that the effects of these two substances are mediated by different receptor/intracellular messengers.
通过电生理学方法记录了201个纹状体神经元对运动皮层刺激的兴奋性反应，以测试褪黑素（aMT）和/或D1及D2拮抗剂的作用。aMT离子导入使68.5%的神经元的兴奋性反应减弱，潜伏期为2 - 4分钟，使11.9%的神经元的兴奋性反应增强；19.6%的神经元反应无变化。舒必利（D2拮抗剂）离子导入使62.8%的神经元的兴奋性反应立即增强，2.3%的神经元反应减弱，34.9%的神经元反应无变化。舒必利的注入抵消了aMT对纹状体神经元兴奋性反应的抑制作用。SCH - 23390（D1拮抗剂）离子导入无显著作用。结果表明，相同的纹状体神经元可能受aMT和D2受体驱动。然而，反应潜伏期的显著差异表明这两种物质的作用是由不同的受体/细胞内信使介导的。
