British journal of pharmacology and chemotherapy
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The vasomotor and cardiac effects of gamma-aminobutyric acid (GABA) administered by different routes were studied in cats and dogs. The cat was resistant to the action of GABA administered intravenously or into a vertebral artery. ⋯ Bradycardia observed after intravenous and intraventricular injections of GABA into dogs was abolished by stellate ganglionectomy but not by vagotomy. It has been attributed to depression of the central sympathetic neurones.
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Br J Pharmacol Chemother · Feb 1963
Facilitation of neuromuscular transmission by anticholinesterase drugs.
A close correlation has been shown to exist between the in vitro anticholinesterase potencies of ambenonium, neostigmine, methoxyambenonium and edrophonium chloride and their abilities to increase muscle contractions produced by close-arterial injections of acetylcholine. No correlation was found between the anticholinesterase potencies of the drugs and their potentiations of the maximal twitch in response to electrical stimulation, or their antagonisms of tubocurarine. It is concluded that some action, in addition to inhibition of cholinesterase, contributed to their facilitation at the neuromuscular junction, and it is suggested that this action may be at the prejunctional site.