| Literature DB >> 5157721 |
Abstract
1. Observations were made on the effects of 4-(m-chlorophenylcarbamoyloxy)-2-butynyltrimethylammonium chloride (McN-A-343) on responses of isolated segments of the central artery of the rabbit's ear to sympathetic nerve stimulation and noradrenaline.2. With low frequencies of nerve stimulation (2-5 Hz), McN-A-343 caused a decrease in responses to sympathetic nerve stimulation. This effect of McN-A-343 was abolished by dexamphetamine or atropine. In the presence of atropine, McN-A-343 caused an increase in responses to sympathetic nerve stimulation.3. With high frequencies of nerve stimulation (10-20 Hz), McN-A-343 caused an increase in responses. This effect was not qualitatively changed in the presence of atropine.4. When McN-A-343 had an inhibitory effect on responses to sympathetic nerve stimulation, responses to noradrenaline were unaffected.5. It is suggested that McN-A-343 acts on muscarinic receptors through which noradrenaline release may be inhibited; it may also act on the cholinergic stage in adrenergic transmission postulated by Burn & Rand (1959).Entities:
Mesh：
Substances：
Year: 1971 PMID： 5157721 PMCID： PMC1665796 DOI： 10.1111/j.1476-5381.1971.tb07183.x
Source DB: PubMed Journal: Br J Pharmacol ISSN： 0007-1188 Impact factor: 8.739