[Effect of a return of motor neurons to spontaneous activity on the multi-innervation of muscular fibers induced in chick embryo by chronic slow-rhythm spinal cord stimulation].

The multi-innervation of posterior latissimus dorsi muscle caused in Chick embryo by chronic spinal cord stimulation at low rhythm (0.5 HZ) from the 10th until 14th day of incubation remains but does not increase if the stimulating period is prolonged. If the stimulating period is stopped and the embryo allowed to develop for several more days the number of acetylcholinerase sites on the muscle fibres decreases. This result suggests that the multi-innervation regresses after the cessation of the experimentally-imposed nervous signal.