Sensory Nerve Endings in Minced Muscle of Young and Old Rats

Abstract

Muscle and tendon sensory innervation plays an important role not only in the fine coordination of motions (Cooper, 1960), but also in the success of skeletal muscle regeneration (Zhenevskaya, 1974; Studitsky, 1977). In the embryogenesis of muscular tissue, the formation of mechanoreceptors is induced by sensory nerve fibers. Their differentiation is completed two to three weeks after the rat’s birth (Zelená, 1964; Milburn, 1973; Zelená and Soukup, 1977). Thus, sensory neurons exert a morphogenetic influence upon muscle at that age. Later, the transmission of impulses from the periphery to the nerve centers is improved in sensory nerve fibers. It was shown that after nerve section performed in newborn rats, muscle mechanoreceptors disintegrated rapidly and did not reappear (Zelená and Hník, 1960). Some tendency to restoration of mechanoreceptors is observed only in two to three-week-old rats (Schiaffino and Pierobon Bormioli, 1976).