电刺激尾核对兔视前区羟戊甲吗啡敏感神经元自发放电的影响

本实验运用多管微电极离子微电泳技术,观察到电刺激家兔尾核头部能影响视前区神经元的自发放电活动。电刺激尾核对视前区羟戊甲吗啡敏感单位的抑制率比较高(P<0.02);微电泳纳洛酮能阻断电刺激尾核的抑制效应,但不能阻断兴奋效应,提示这种抑制效应与视前区内阿片肽的活动有关。但未能看到电刺激尾核的效应与微电泳去甲肾上腺素的效应之间的相关关系。 进一步的观察及统计分析表明,电针及电刺激尾核对视前区羟戊甲吗啡敏感单位的共同抑制率明显高于羟戊甲吗啡不敏感单位(P<0.05),提示视前区的一部分羟戊甲吗啡敏感神经元,可能是这两种刺激的共同作用点之一。

EFFECT OF CAUDATE STIMULATION ON ETORPHINE-SENSITIVE NEURONES IN RABBIT PREOPTIC AREA

Experiments were performed on rabbit preoptic area with the techniques ofmultimicropipettes and microiontophoresis to investigate the effect of caudatestimulation. Caudate stimulation could affect the spontaneous discharges in mostneurones recorded from the preoptic area. Most etorphine-sensitive neurones couldbe inhibited by caudate stimulation (P<0.02). Microiontophoretic naloxonereversed the inhibitory effect of caudate stimulation, but could not reverse theexcitatory one. The results suggest that the inhibitory effect of caudate stimulationis related to the activity of endogenous opioid peptides in the preoptic area. How-ever, there was no correlation between the effect of microiontophoretic noradrenalineand that of caudate stimulation in the experiments. The effects of iontophoretic etorphine, electroacupuncture and caudate stimula-tion were compared. It was found that the common inhibitory rate of electroacu-puncture and caudate stimulation was higher in the etorphine-sensitive neuronesthan in the other neurones (P<0.05), suggesting that some etorphine-sensitiveneurones in the preoptic area may be one of the common targets for electroacu-puncture and caudate stimulation.