A new beta-adrenoceptor blocking agent derived from dehydrozingerone.
1. Dehydrozingeronolol (DZPN; 0.1, 0.5, 1.0 mg/kg, i.v.) produced a dose-dependent bradycardia response and a sustained pressor action in urethane-anesthetized normotensive rats. DZPN inhibited the tachycardia effects by (-)isoproterenol, but had no blocking effect on the arterial pressor responses induced by phenylephrine. 2. In in vitro study, DZPN antagonized (-)isoproterenol-induced positive chronotropic effects in guinea-pig isolated right atria and relaxation responses in rat isolated uterus horns. 3. DZPN causes mild direct cardiac depression at high concentrations without intrinsic sympathomimetic activity (ISA). 4. The order of potency of beta-adrenoceptor antagonists in competing for the [3H]dihydroalprenolol binding sites was (-)propranolol >> DZPN > or = atenolol.
Wu
B N
BN
Department of Pharmacology, Kaohsiung Medical College, Taiwan, Republic of China.
Yang
C R
CR
Yang
J M
JM
Chen
I J
IJ
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002074:Butanones / Q000494:pharmacology*; D004082:Dihydroalprenolol / Q000378:metabolism; D005260:Female; D006168:Guinea Pigs; D006339:Heart Rate / Q000187:drug effects; D066298:In Vitro Techniques; D008297:Male; D011412:Propanolamines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D018342:Receptors, Adrenergic, beta-1 / Q000187:drug effects; D018343:Receptors, Adrenergic, beta-2 / Q000187:drug effects; D013343:Styrenes / Q000737:chemistry
D000319:Adrenergic beta-Antagonists; D002074:Butanones; D011412:Propanolamines; D018342:Receptors, Adrenergic, beta-1; D018343:Receptors, Adrenergic, beta-2; D013343:Styrenes; C090353:dehydrozingeronolol; D004082:Dihydroalprenolol; C052933:methyl-3-methoxy-4-hydroxystyryl ketone