Subacute effects of propranolol and B 24/76 on isoproterenol-induced rat heart hypertrophy in correlation with blood pressure.
We compared the potential beta-receptor blocker, B 24/76 i.e. 1-(2,4-dichlorophenoxy)-3[2-3,4-dimethoxyphenyl)ethanolamino]-prop an-2-ol, which is characterized by beta 1-adrenoceptor blocking and beta 2-adrenoceptor stimulating properties with propranolol. The studies were performed using an experimental model of isoproterenol-induced heart hypertrophy in rats. A correlation of the blood pressure was neither found in the development nor in the attempt to suppress the development of heart hypertrophy with the two beta-receptor blockers. Both beta-blockers influenced the development of hypertrophy to a different, but not reproducible extent. It was possible to suppress the increased ornithine decarboxylase activity with both beta-blockers in hypertrophied hearts, but there was no effect on the heart mass. Neither propranolol nor B 24/76 could stop the changes in the characteristic myosin isoenzyme pattern of the hypertrophied rat heart. Thus, the investigations did not provide any evidence that the beta-receptor blockers propranolol and B 24/76 have the potency to prevent isoproterenol from producing heart hypertrophy.
Grisk
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Institute of Pharmacology and Toxicology, Ernst Moritz Arndt University, Greifswald, GDR.
Hoffmann
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U
Möritz
K U
KU
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects*; D006332:Cardiomegaly / Q000139:chemically induced / Q000188:drug therapy*; D007527:Isoenzymes / Q000378:metabolism; D007545:Isoproterenol / Q000633:toxicity*; D009218:Myosins / Q000378:metabolism; D009955:Ornithine Decarboxylase / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
D007527:Isoenzymes; D011433:Propranolol; D009218:Myosins; D009955:Ornithine Decarboxylase; D007545:Isoproterenol