用辣根过氧化酶法研究大白鼠尾核头部自皮质下核团的传入联系

THE AFFERENT CONNECTIONS TO THE HEAD OF THE CAUDATE NUCLEUS OF RAT FROM SUBCORTICAL NUCLEI.AN EXPERIMENTAL STUDY OF AXONAL RETROGRADE TRANSPORT OF HORSERADISH PEROXIDASE

从七十年代初期,在研究神经系统联系方面,又增加了一个新的辣根过氧化酶(HRP)轴突逆行传递法^([1])。将HRP注入中枢或周围一定部位,分布于该部的轴突末梢可以吸入HRP并将它沿轴突传至远隔的细胞体。近年来,这个方法已广泛得到应用。在我国首见郑则慧和毛金标用此法研究了大白鼠和猫的尾、壳核的传入联系^([2])。尾核已被表明是参与针刺镇痛的一个重要部位^([3~5])。深入研究尾核的神经联系,对阐明针刺镇痛机制会有所助益。

The afferent projections to the head of the caudate nucleus of rat from subcortical nuclei were studied with the method of retrograde axonal transport of horseradish peroxidase(HRP).Experiment were carried out in a series of adult rat.Under pentobarbital sodium anesthesia,0.2~0.5,μl of 50%solution of HRP was injected slowly into the head of the caudate nucleus of the rat.according to the stereotaxic atlas by Massopust,Jr.After a survival time of 6~72 h,the animals were perfused with fixative solution(1.25%glutaraldehyde and 2.0%paraformaldehyde in 0.1M phosphate buffer,at pH 7.4).The brain was removed and then postfixed in same fixative at 4℃for 6~18h.The frozen sections were incubated in a medium containing 3,3′-diaminobenzidine tetrahydrochloride and hydrogen peroxide.The sections were examined microscopically under both bright-field and dark-field illumination.Labelled neurons were found ipsilaterally in the parafascicular nucleus of the thalamus and substantia nigra of the midbrain.They were also found in the dorsal nucleus of the midbrain raphe,mainly ipsilaterally,scantily contralaterally.Statistical examination showed as follows:The substantia nigra of the midbrain has the most labelled neurons,the dorsal nucleus of the midbrain raphe has the least labelled neurons,while the parafascicular nucleus of the thalamus has moderate number of labelled neurons.The afferent projections to the head of the caudate nucleus of the rat from the subcortical nuclei may play the role in the mechanism of pain and pain control.