Subramani V, Sahgal V, Sahgal S, Shah A
Exp Brain Res. 1986;64(1):149-57. doi: 10.1007/BF00238211.
The pre- and postsynaptic structure of 243 axon terminals of bag 1, bag 2, and chain fibers were studied in cynomolgus monkey skeletal muscle spindles. The motor endings of the biceps and gastrocnemius spindles (long limb muscle) were compared to the motor endings of lumbricals and opponens pollicis (intrinsic hand muscle) spindles. In both muscle groups the only significant difference observed in the presynaptic features was in the presynaptic membrane length. The postsynaptic features of bag 1, bag 2 and chain endings were similar in the long limb muscle spindles. In the intrinsic hand muscle, however, the bag 1 and chain endings showed complex postsynaptic structure which resembled the extra fusal endings while the postsynaptic structure of bag 2 endings was much simpler. From these studies we conclude that the postsynaptic structure of various intrafusal fiber types is dissimilar in different muscles.
在食蟹猴骨骼肌纺锤体中，对243个袋1、袋2和链纤维轴突终末的突触前和突触后结构进行了研究。将肱二头肌和腓肠肌纺锤体（长肢肌）的运动终末与蚓状肌和拇对掌肌（手部固有肌）纺锤体的运动终末进行了比较。在这两组肌肉中，突触前特征方面观察到的唯一显著差异在于突触前膜长度。长肢肌纺锤体中袋1、袋2和链终末的突触后特征相似。然而，在手部固有肌中，袋1和链终末显示出复杂的突触后结构，类似于梭外终末，而袋2终末的突触后结构则简单得多。从这些研究中我们得出结论，不同肌肉中各种梭内纤维类型的突触后结构是不同的。
