Central sympathoinhibitory action of a new type of alpha-1 adrenoceptor antagonist, YM-617, in rats.

Abstract

The structurally new type of alpha-1 adrenoceptor antagonist, YM-617 [R-(-)-5-[2-[(2-(o-ethoxyphenoxy)ethyl]amino)propyl]-2- methoxybenzenesulfonamide hydrochloride], is a phenethylamine derivative which is similar structurally to the catecholamines. The present study was undertaken to elucidate the effect of YM-617 on sympathetic nerve activity and baroreceptor afferent nerve activity in anesthetized rats. Intravenous administration of YM-617 (2, 10 and 50 micrograms/kg) produced a dose-dependent reduction in mean arterial pressure accompanied with bradycardia. YM-617 caused dose-dependent decreases in renal sympathetic nerve activity along with this hypotension. Cardiac sympathetic nerve activity, preganglionic adrenal nerve activity as well as aortic depressor nerve activity was decreased by YM-617. When an equihypotensive dose of YM-617 and a centrally acting antihypertensive drug, clonidine, were compared, the sympathoinhibitory potency of YM-617 was less than that of clonidine. These findings suggest that YM-617 might possess a central sympathoinhibitory action which could play a role in its antitachycardic or bradycardic effect and could be partially responsible for its hypotensive action.

• Authors: M Yoshioka, H Togashi, M Abe, T Ikeda, M Matsumoto, H Saito
• Journal: The Journal of pharmacology and experimental therapeutics (J Pharmacol Exp Ther) Vol. 253 Issue 2 Pg. 427-31 (May 1990) ISSN: 0022-3565 [Print] United States
• PMID: 1692588 (Publication Type: Journal Article)

Chemical References

• Adrenergic alpha-Antagonists
• Sulfonamides
• RNA
• YM 12617
• Clonidine

Topics

• Adrenergic alpha-Antagonists (pharmacology)
• Animals
• Blood Pressure (drug effects)
• Clonidine (pharmacology)
• Electrophysiology
• Heart Rate (drug effects)
• Injections, Intravenous
• Male
• RNA (analysis)
• Rats
• Rats, Inbred Strains
• Sulfonamides (pharmacology)
• Sympathetic Nervous System (drug effects)