Following sciatic nerve crush the restoration of neuromuscular transmission in the extensor digitorum longus muscle of rat proceeds in a well defined manner: 1. (a) as soon as the nerve-muscle contact is reformed, a subthreshold end-plate potential is recorded; no 'non-transmitting stage' is observed; 2. (b) 24hours later muscle action potentials are induced by nerve stimulation; 3. (c) miniature end-plate potentials are absent or very rare at the newly reinnervated end-plates; their frequency returns to normal in about 4 weeks; 4. (d) the frequency is also very much reduced in 30 mM K+ and hypertonic solutions and recovers slowly, in 4 and 5 weeks, respectively, while black widow spider venom is from the beginning as powerful as in normal neuromuscular junctions; 5. (e) at the early stages of reinnervation the Ca2+-dependent release mechanisms are much stronger than control cases, while the Ca2+-independent mechanisms are weaker and recover in 5 weeks. The gradual reassembly and restoration of neurotransmitter release mechanisms of the extensor digitorum longus nerve terminal indicate the complexity of pre-synaptic ending organization.
|Titolo:||Muscle reinnervation—I. Restoration of transmitter release mechanisms|
GORIO, ALFREDO (Ultimo)
|Settore Scientifico Disciplinare:||Settore BIO/14 - Farmacologia|
|Data di pubblicazione:||1983|
|Digital Object Identifier (DOI):||10.1016/0306-4522(83)90187-2|
|Appare nelle tipologie:||01 - Articolo su periodico|