Pharmacodynamic effects of a 2-piperazinotetralin (P-11)--combined alpha- and beta-adrenoceptor blocking drug with hypotensive action.
The piperazinotetralin derivative P-11 at hypotensive doses of 0.25 to 1.00 mg/kg i.v. reduced the pressor effects of exogenous noradrenaline (10 micrograms/kg i.v.) in reserpine-pretreated rats, but was ineffective in nonreserpinized normotensive urethane-anesthetized rats. P-11 (0.25 to 1.00 mg/kg i.v.) decreased the positive chronotropic effects of isoprenaline (0.2 micrograms/kg i.v.), but potentiated the isoprenaline-induced hypotension in reserpine-pretreated rats. P-11 (10(-7) to 10(-5)M) did not modify the concentration-effect curves for isoprenaline in carbachol-contracted guinea-pig tracheal strips. The pD2 value of isoprenaline was 5.94 before and 6.35 after P-11. The combined alpha1-postsynaptic antagonist/beta1-blocking activity of this compound is discussed.
Mutafova-Yambolieva
V
V
Department of Experimental Pharmacology, Bulgarian Academy of Sciences, Sofia.
Staneva-Stoytcheva
D
D
D015081:2-Naphthylamine / Q000031:analogs & derivatives / Q000494:pharmacology*; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology*; D001794:Blood Pressure / Q000187:drug effects; D006168:Guinea Pigs; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D009281:Naphthalenes / Q000494:pharmacology*; D010646:Phentolamine / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D014132:Trachea / Q000187:drug effects
D000317:Adrenergic alpha-Antagonists; D000319:Adrenergic beta-Antagonists; D000959:Antihypertensive Agents; D009281:Naphthalenes; C023611:N-(3-hydroxy-1,2,3,4-tetrahydro-2-naphthyl)-N-(3-oxo-3-phenyl-2-methylpropyl)piperazine; D015081:2-Naphthylamine; D007545:Isoproterenol; D010646:Phentolamine