title: End-plate growth exceeds nerve terminal growth in juvenile mice.
abstract: An electron microscopic investigation of neuromuscular synapses of the tensor fasciae latae muscle in juvenile mice was carried out to determine the relationship between the presynaptic (nerve terminal) and postsynaptic (end-plate plaque) elements during the major phase of postnatal growth. In the first month of life growth of the synapse was accompanied by a decrease in the size of pre- and postsynaptic elements in cross section. A decrease in the fraction of the width of end-plate plaque opposed by nerve terminal was also observed to age 2 months, and in older animal some end-plate plaques were completely unopposed by nerve terminal. This implies that end plates grow at a faster rate than nerve terminals and suggests that the availability of uninnervated, differentiated end plate permits or promotes nerve terminal growth.
mesh_terms: D000375:Aging / Q000502:physiology; D000818:Animals; D051379:Mice; D008854:Microscopy, Electron; D009045:Motor Endplate / Q000254:growth & development* / Q000648:ultrastructure; D009411:Nerve Endings / Q000254:growth & development* / Q000648:ultrastructure; D009469:Neuromuscular Junction / Q000254:growth & development*