Vaninolol: a new selective beta 1-adrenoceptor antagonist derived from vanillin.

Abstract

The beta-adrenoceptor blocking properties of vaninolol ((+/-)4-[4'-(2-hydroxy-3-tert-butyl-aminopropoxy)-3'-methoxyphenyl]- 3-buten-2-one), derived from vanillin, were first investigated under in vivo and in vitro conditions. Vaninolol (0.1, 0.5, 1.0 mg/kg, i.v.), as well as propranolol, produced a dose-dependent bradycardia response and a sustained pressor action in urethane-anesthetized normotensive rats. Vaninolol inhibited the tachycardia effects induced by (-)isoproterenol, but had no blocking effect on the arterial pressor responses induced by phenylephrine. These findings suggested that vaninolol possessed beta-adrenergic blocking activity, but was without alpha-adrenergic blocking activity. In isolated guinea-pig tissues, vaninolol antagonized (-)isoproterenol-induced positive inotropic and chronotropic effects of the atria and tracheal relaxation responses in a concentration-dependent manner. The parallel shift to the right of the concentration-response curve of (-)isoproterenol suggested that vaninolol was a beta-adrenoceptor competitive antagonist. The effect of vaninolol was more potent on the atria than on tracheal tissues, indicating it had some beta 1-adrenoceptor selectivity. On the other hand, the order of the hydrophilicity was atenolol >> vaninolol > propranolol. In addition, vaninolol had a mild direct cardiac depression at high concentrations and was without intrinsic sympathomimetic activity (ISA). Furthermore, binding characteristics of vaninolol and other beta-adrenoceptor antagonists were evaluated in [3H]dihydroalprenolol binding to guinea-pig ventricular membranes. The order of potency of beta-adrenoceptor antagonists in competing for the binding sites was (-)propranolol >> vaninolol > or = atenolol. In conclusion, vaninolol was found to be a selective beta 1-adrenoceptor antagonist with relatively low lipophilicity in comparison with propranolol, devoid of ISA, and had a mild myocardial depressant effect.

• Authors: B N Wu, T L Hwang, C F Liao, I J Chen
• Journal: Biochemical pharmacology (Biochem Pharmacol) Vol. 48 Issue 1 Pg. 101-9 (Jul 05 1994) ISSN: 0006-2952 [Print] England
• PMID: 8043010 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Adrenergic beta-1 Receptor Antagonists
• Benzaldehydes
• Butanones
• Propanolamines
• Sympathomimetics
• vaninolol
• vanillin

Topics

• Adrenergic beta-1 Receptor Antagonists
• Animals
• Benzaldehydes (chemistry)
• Blood Pressure (drug effects)
• Butanones (isolation & purification, pharmacology)
• Female
• Guinea Pigs
• Heart Rate (drug effects)
• In Vitro Techniques
• Male
• Propanolamines (isolation & purification, pharmacology)
• Radioligand Assay
• Rats
• Rats, Wistar
• Sympathomimetics (pharmacology)