【摘要】 <正> 许多资料证明,针刺感觉由外周神经传入中枢,经过脊髓、脑干和丘脑各级水平的整合,达到抗痛的目的。针刺具有复杂的调整作用,它既能激发某些神经元的功能,又要抑制另一些神经元的功能,而神经递质正是实现这两方面作用的重要物质基础。因此,研究神经递质在针刺过程中的变化规律颇受大家的重视。本文部分工作者曾用5、6-双羟色胺选择性损毁猫脑内5-羟色胺(5-HT)神经元功能后,观察到针刺镇痛因此更多还原

【Abstract】 Since neurotransmitters play an important role in many physiological functions,the elucidation of their interactions will greatly help to understand the mechanismof acupuncture analgesia.This paper reported the relationships between theaction of brain monoaminergic systems and acupuncture analgesia in rats by meansof several neuropharmacological manipulations.The results were summarized asfollows:(1)The inhibition of brain,serotonergic system could abolish acupunctureanalgesia:In rats treated with P-chloroamphetamine(PCA, 5mg/kg),the brain5-HT and 5-HIAA,as well as the effect of acupuncture analgesia were markedlyreduced.in another group after injection of 20 mg/kg of cinanserin,the effect ofacupuncture analgesia in each of 11 rats was almost abolished.From the above-mentioned evidences,it is indicated that the normal activity of brain sero-tonergic neurons is necessary for acupuncture analgesia.(2)Augmentation of brain 5-HT neuronal activity could increase the effectof acupuncture analgesia:The experiments have shown that acupuncture analge-sia was accompanied with the augmentation of 5-HT neuronal activity,of whicha valid index was the elevation of brain 5-HIAA levels.In two groups of rats pretreated with PCA,one group was then stimulatedby acupuncture,but another was not.The brain levels of 5-HT and 5-HIAA in theformer group were increased much more than those in the latter.It was alsodemonstrated that dl-5-HTP(75 mg/kg)caused the elevation of the concentrationsof 5-HT and 5-HIAA inrat brain.In other rats administered previously with 5-HTP,after acupuncture the brain levels of 5-HT and 5-HIAA were raised more than thatof the control group,to which 5-HTP Was given only.From these findings,it isdeduced that acupuncture could activate tryptophan hydroxylation and5-HTP decarboxylation in 5-HT biosynthesis,and at the same time augment theoxidative deamination of 5-HT catabolism. (3)The effect of noradrenaline on acupuncture analgesia:After acupuncturebrain noradrenaline contents were decreased significantly,while dopamineconcentrations were found unchanged.The analgesic effect of acupunture was not potentiated in rats pretreatedWith either α-rapt,sodium diethyldithiocarbamate(DDC)or phenoxybenzamine(PBZ).After the combined administration of DDC+PBZ(500+10mg/kg),the brain NA contents of rats decreased markedly,while the 5-HIAA and DAlevels were not affected.In these,animals on only a potentiation of post-effect ofacupuncture analgesia was observed.Considering the above mentioned paradoxical results,it is suggested thatthe role of NA on acupuncture analgesia might be complicated,and the localinjection of drugs into brain would be very important for studying the functionalspecificity.(4)The modulation of noradrenergic neurons on serotonergic neurons:DDCcaused a pronounced depletion of brain NA,but an elevation of brain 5-HIAAlevel;the latter could be abolished by the combined administration of DDC+PBZ.Hence,it may be suggested thai the regulatory influence on the 5-HT neuronalactivity exerted by the noradrenergic system might be mediated by α-adreno-receptors.更多还原