70年代以来

许多学者认为肌梭是肌肉丰厚处穴位内针感感受器

因而对肌梭的研究颇为广泛。我们也曾对穴位内肌梭的微细结构进行了论述。为进一步探讨针麻原理及配合肌肉移植后其功能恢复的研究

本文又对人涌泉穴区内肌梭的超微结构进行了观察。材料和方法材料取自20例病人截除下肢涌泉穴深部的足蚓状肌

稍伸展后系于玻棒上

前固定于预冷的2％多聚甲醛——2.5％戊二醛磷酸缓冲液中24小时(2～4℃)

磷酸缓冲液(pH7.2～7.4)浸洗数小时

将蚓状肌切成2～3段

每段用半导体冷冻切片机纵切The ultrastructure of the muscle spindles obtained from the area of 20 human Yongquan points was observed by transmission and cryofracture scanning electron microscope. It was revealed that capsule of the muscle spindle was divided into outer and inner layers by a subcapsular space

while the outer capsule was consisted of more than ten layers of flattened membranous fibroblasts and collagenous fibrils between them

and the inner capsule was only consisted of several extremely flattened fibroblasts surro- und every intrafusal muscle fiber. The intrafusal muscle fibers may be di- vided clearly into nuclear bag and nuclear chain fibers by both TEM and SEM. The primary sensory endings on the nuclear bag region of the nuclear bag fibers were partially covered by two lips of sarcolemma

while those located on the nuclear chain fibere were not. Satellite cells on the myotube region of the nuclear bag fibers were demonstrated.Small vascular and capil- laries were found both in the outer capsule between membranous layers as well as in the subcapsular cavity.