Antagonistic activity of etizolam on platelet-activating factor in vivo experiments.

Abstract

The ability of etizolam, 6-(o-chlorophenyl)-8-ethyl-1-methyl-4H-s-triazolo[3,4-c]thieno[2,3-e] [1,4]diazepine (Y-7131), an anti-anxiety drug, to inhibit platelet-activating factor (PAF)-induced reactions was investigated in experimental animals in vivo. Etizolam (0.01-0.3 mg/kg, i.v.) dose dependently inhibited PAF (0.3 microgram/kg, i.v.)-induced bronchoconstriction (Konzett and Rössler's method) in guinea pigs, but even at doses as large as 3 mg/kg, i.v., it had no effect on bronchoconstriction induced by histamine, serotonin, acetylcholine, arachidonic acid, bradykinin, angiotensin l or leukotriene D4. Etizolam (0.1-1 mg/kg, i.v.) also dose-dependently reversed PAF (1 microgram/kg, i.v.)-induced hypotension in anesthetized rats. Injection of PAF into the tail veins of mice produced lethal shock within 10-30 min. Etizolam (0.1-3 mg/kg, i.v. and 1-10 mg/kg, p.o.) protected against the lethal effect of PAF (75 micrograms/kg, i.v.) in a dose-dependent manner. These results indicate that etizolam specifically inhibits the action of PAF in vivo.

• Authors: M Terasawa, H Mikashima, T Tahara, Y Maruyama
• Journal: Japanese journal of pharmacology (Jpn J Pharmacol) Vol. 44 Issue 4 Pg. 381-6 (Aug 1987) ISSN: 0021-5198 [Print] Japan
• PMID: 3682404 (Publication Type: Journal Article)

Chemical References

• Bronchodilator Agents
• Platelet Activating Factor
• Tranquilizing Agents
• etizolam
• Diazepam

Topics

• Animals
• Blood Pressure (drug effects)
• Bronchi (drug effects)
• Bronchodilator Agents
• Diazepam (analogs & derivatives, pharmacology)
• Female
• Guinea Pigs
• Lethal Dose 50
• Male
• Mice
• Mice, Inbred ICR
• Platelet Activating Factor (antagonists & inhibitors)
• Rats
• Species Specificity
• Tranquilizing Agents (pharmacology)