Relationship between the partitioning properties of motoneuron recruitment and the needle feeling propagation

Histological and physiological studies indicated that most skeletal muscles can be divided into a series of relatively independent sub-volumes: “neuromuscular compartments” and the partitioning property of the muscle result in the localization of muscle reflex. In the present experiment we studied the recruitment properties of medial gastracnemius (MG) muscle motoneumn pool of decerebrate cat with two kinds of local mechanical stimulation: local stretch and acupuncture-like stimuli. The results indicate that: (I) there is an obvious property of localization of recruitment activity, only the MNs which innervate the stimulated compartment were recruited by weaker and shorter stimuli; (ii) recruitment activity spread to those MNs which supply the adjacent and distal compartments during the strength of stimulation or duration of the stimulation was increased; and (iii) the recruitment property of muscle activity elicited by the local mechanical stimulation is thought similar to that of “needle feeling” along the meridian pathway during stimulation of acupuncture point.