The autonomic margins of safety of metocurine and d-tubocurarine in the cat.

TitleThe autonomic margins of safety of metocurine and d-tubocurarine in the cat.
Publication TypeJournal Article
Year of Publication1979
AuthorsSavarese JJ
JournalAnesthesiology
Volume50
Issue1
Pagination40-6
Date Published1979 Jan
ISSN0003-3022
KeywordsAnimals, Autonomic Nerve Block, Autonomic Nervous System, Cats, Dose-Response Relationship, Drug, Drug Evaluation, Preclinical, Female, Histamine Release, Male, Neuromuscular Junction, Synaptic Transmission, Tubocurarine
Abstract

The potencies of metocurine and d-tubocurarine for neuromuscular and autonomic blockade and histamine release were determined in cats anesthetized with chloralose and pentobarbital. The autonomic margins of safety of these drugs were determined by measuring the ratios of ED50 for sympathetic block to ED95 for neuromuscular block; ED50 for vagal block to ED95 for neuromuscular block; ED50 for histamine release to ED95 for neuromuscular block. Metocurine is 14 times more potent than d-tubocurarine as a neuromuscular blocking agent in the cat, but its autonomic blocking action is three times weaker than the of d-tubocurarine and its histamine-releasing action is less than half that of d-tubocurarine. The combination of higher neuromuscular blocking potency and weaker autonomic effect gives metocurine a much higher autonomic margin of safety than d-tubocurarine in the cat.

Alternate JournalAnesthesiology
PubMed ID83803