吗啡、MK-801对电刺激隐神经引起大鼠ACG多巴胺含量增高的影响

Influence of morphine or MK-801 to the increase in dopamine content in rats ACG induced by stimulating SN

目的研究皮下注射吗啡、静脉注射N-甲基-D-天冬氨酸(N-methyl-D-aspartate,NMDA)受体拮抗剂5-甲基二氢丙环庚烯马来酸(MK-801)对电刺激隐神经(saphenous nerve,SN)引起大鼠扣带回前部(anterior cingulate gyrus,ACG)多巴胺含量增高的影响,以及MK-801对吗啡作用的影响。方法应用高效液相色谱-电化学检测技术进行实验研究。结果电刺激SN引起ACG多巴胺含量显著增高;皮下注射吗啡抑制电刺激SN引起的ACG多巴胺含量的显著增高;静脉注射MK-801能够拮抗电刺激SN引起的ACG多巴胺含量的显著增高,并且能够增强吗啡抑制电刺激SN引起的ACG多巴胺含量的显著增高。结论 SN传导的伤害性信息能够到达ACG,激活ACG多巴胺能神经元,释放多巴胺,谷氨酸NMDA受体参与此过程;吗啡抑制ACG多巴胺能神经元的活动;MK-801增强吗啡的抑制作用。

Objective To investigate influence of morphine or MK-801 to the increase in dopamine （DA） content in rats anterior cingulate gyrus （ACG） induced by electrically stimulating saphenous nerve （ SN）, and effect of MK-801 on the action of morphine. Methods High performance liquid chromatography electro- chemical detection was used to measure DA content in ACG. Results Electrically stimulating SN caused ob- vious increase in DA content in ACG. Subcutaneous injection of morphine inhibited the significant increase in DA content in ACG induced by electrically stimulating SN. MK-801 intravenous injection antagonized the obvious increase in DA content in ACG induced by electrically stimulating SN, and increased the action of morphine on inhibiting the significant increase in DA content in ACG induced by electrically stimulating SN. Conclusions These findings suggest that nocuity afferent signals of SN can reach ACG, and activate the dopaminergic neurons in ACG to release DA. NMDA receptors are involved in the process of increases in DA content in rats ACG. Morphine inhibited the action of the dopaminergic neurons in ACG. MK-801 aug- mented the inhibited action of morphine.