脊髓灰质向中缝大核的纤维投射——HRP法

PROJECTIONS TO THE NUCLEUS RAPHE MAGNUS FROM THE SPINAL GRAY MATTER IN THE RAT(HRP METHOD)

本实验用微玻管将50%HRP 0.02微升注入12例大白鼠中缝大核,从颈髓到骶髓均可见到标记细胞,腰段较多;分布于双侧Ⅱ板层至Ⅹ板层,以Ⅶ板层为最多,其次为Ⅴ板层,Ⅳ板层居第三位,总的分布为Ⅶ层>Ⅴ层>Ⅳ层>Ⅲ层>Ⅷ层>Ⅹ层>Ⅵ层>Ⅸ层>Ⅱ层。标记细胞形态有圆形、卵圆形、多角形及梭形等。多数在20—40微米之间,占标记细胞总数的61%,大于40微米者占12%,小于20微米者占27%。本实验证明脊髓灰质向中缝大核的投射较为广泛,为中缝大核针刺镇痛的机理提供了形态学依据,同时讨论了脊髓灰质—中缝大核纤维联系的生理意义。

We further studied the afferent projections to the nucleus raphe magnus(RM)from the spinal gray matter in the rat by means of using the horseradish peroxidase(HRP)retrograde tracing method.After HRP was injected into RM,the labelled cells were observed bilaterally in spinal gray matter from cervical to sacral segments.The distribution of the labelled cells in the spinal gray matter was from lamina Ⅱ to lamina Ⅹ.Of the labelled cells,the largest number was observed in lamina Ⅶ.The percentage of the labelled cells was 37.2%in lamina Ⅶ,28.0%in lamina Ⅴ,12.0%in lamina Ⅳ,8.9%in lamina Ⅲ,5.0%in lamina Ⅷ,3.0%in laminaⅩ,2.4%in lamina Ⅵ,2.0%in lamina Ⅸ,and 1.5%in lamina Ⅱ.Most of the labelled cells were medium(61%)or small(27%)in size and var ied in form(fusiform,round and star-shaped).This study provided a foundation for explaining the mechanism of acupuncture analgesia by stimulating RM.Other physiologic functions of RM concerning the present results were also discussed.