Neuromuscular plasticity in the locust after permanent removal of an excitatory motoneuron of the extensor tibiae muscle.

摘要: The capacity of the larval insect nervous system to compensate for permanent loss one two excitatory motoneurons innervating a leg muscle was investigated in locust (Locusta migratoria). In fourth instar, fast extensor tibiae (FETi) motoneuron mesothoracic ganglion permanently removed by photoinactivation with helium-cadmium laser. Subsequently, animals were allowed develop into adulthood. When experimental tested as adults after final ecdysis, fast-contracting fibers most proximal region corresponding muscle, which are normally predominantly innervated FETi only, uniformly responded activity slow (SETi) neuron. adult operated animals, single pulses SETi elicited large junctional responses resulted twitch contractions these similar control animals. total number fibers, their properties histochemically determined contractional types (fast and slow), distribution not affected FETi. Possible mechanisms enabling neuromuscular through functionally innervation different motoneuron, i.e. SETi, discussed.