The pharmacological basis of coronary and systemic vasodilator actions of diazepam (Valium)

• Published in: British journal of pharmacology Vol. 39; no. 2; pp. 261 - 274
• Main Authors: ABEL, R. M., REIS, R. L., STAROSCIK, R. N.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.06.1970
• Subjects: Animals; Atropine - pharmacology; Blood Flow Velocity; Blood Pressure - drug effects; Coronary Vessels - drug effects; Diazepam - pharmacology; Dogs; Phenoxybenzamine - pharmacology; Propranolol - pharmacology; Reserpine - pharmacology; Systematic Pharmacology; Trimethaphan - pharmacology; Vagotomy; Vascular Resistance - drug effects
• ISSN: 0007-1188; 1476-5381
• DOI: 10.1111/j.1476-5381.1970.tb12890.x

Summary 1 The effects of α and β‐adrenoceptor blockade, depletion of catecholamine stores, vagotomy, atropine, and ganglionic blockade on diazepam‐induced vasodilatation were investigated in forty‐six anaesthetized dogs. 2 Coronary blood flow was measured by timed collections of coronary venous efflux from fibrillating, decompressed ventricles; coronary and systemic vascular resistances were determined during total cardiopulmonary bypass under conditions of normothermia and constant aortic (coronary artery) pressure. 3 No significant alteration in the vasodilatation produced by diazepam was observed following either vagotomy or α‐adrenoceptor blockade; partial inhibition of vasodilatation occurred after β‐adrenoceptor blockade or catecholamine depletion, and nearly total inhibition was observed after small doses of atropine or ganglion‐blocking agents. 4 The results suggest that diazepam may act as a specific ganglion‐stimulant, causing active sympathetic and cholinergic vasodilatation.