Neuromuscular blocking activity of a glycosidic extract of the plant Sarcolobus globosus.
Crude glycoside extracts from the plant, Sarcolobus globosus, were tested on the rat phrenic nerve-diaphragm, chick biventer cervicis and frog rectus abdominis preparations. Nerve-stimulated twitches were inhibited by the extract. The muscle paralysis was not similar to that by curare-like blockers as it was not reversed by neostigmine or by a tetanus. Although contractures to acetylcholine or carbachol were not affected by 0.6 mg/ml of the extract, higher concentration of the extracts (3 mg/ml) depressed the log dose-response curve of acetylcholine and carbachol. The results suggest that the neuromuscular blocking effect of the extracts is either dose-dependent or due to a mixture of toxins with presynaptic or postsynaptic actions.
Mustafa
M R
MR
Department of Pharmacology, University Malaya, Kuala Lumpur.
Hadi
A H
AH
D000818:Animals; D002645:Chickens; D006027:Glycosides / Q000494:pharmacology*; D009466:Neuromuscular Blocking Agents / Q000494:pharmacology*; D009469:Neuromuscular Junction / Q000187:drug effects*; D010936:Plant Extracts / Q000494:pharmacology*; D011898:Ranidae; D051381:Rats; D012639:Seeds
D006027:Glycosides; D009466:Neuromuscular Blocking Agents; D010936:Plant Extracts