[The action of non-depolarizing muscle relaxants on nerve terminal of motor endplate--relationship between run-down of endplate potentials and fading tension response].
The classical view of the neuromuscular transmission is that non-depolarizing muscle relaxants (MRs) enhance run-down of the endplate potentials (epps) by blocking pre-junctional nicotinic acetylcholine (ACh) receptors. Several recent investigations, when extended to pharmacology, have provided evidence to suggest the existence of other types of enhancement of run-down of epps by MRs; the enhancement of epps occurs without reduction of ACh release in the presence of MRs. It has been generally accepted that the enhancement of run-down of epps causes the tetanic fade of tension response. However, recent evidence indicates that run-down of epps does not always cause this wane in tension. The electrophysiological mechanism of run-down of epps at the neuromuscular junction and the relationship between that phenomenon and the extent of reduction of tension response are described based on a review of literature and our current investigations.
Narimatsu
E
E
Department of Anesthesiology, Sapporo Medical University, School of Medicine.
Iwasaki
H
H
Namiki
A
A
D000109:Acetylcholine / Q000378:metabolism; D000200:Action Potentials / Q000187:drug effects; D006801:Humans; D009045:Motor Endplate / Q000187:drug effects*; D009119:Muscle Contraction / Q000187:drug effects*; D009411:Nerve Endings / Q000187:drug effects; D009469:Neuromuscular Junction / Q000187:drug effects*; D003473:Neuromuscular Nondepolarizing Agents / Q000494:pharmacology*; D011950:Receptors, Cholinergic / Q000187:drug effects; D009435:Synaptic Transmission / Q000187:drug effects
D003473:Neuromuscular Nondepolarizing Agents; D011950:Receptors, Cholinergic; D000109:Acetylcholine