N-dimethylisopropyl propranolol. Effects on myocardial oxygen demands

Circulation
E G OlsonS Wolfson

Abstract

N-Dimethylisopropyl propranolol (DMP) is a quaternary derivative which lacks significant beta-adrenergic blocking and local anesthetic effects. It has been reported, nonetheless, to be effective in treating experimental arrhythmias and in limiting the extent of ST-segment elevations following experimental coronary occlusion. The present study examined the effects of DMP on the hemodynamics and myocardial oxygen demands of anesthetized dogs. After a single dose of 3 mg/kg, heart rate fell from 146 +/- 8 to 124 +/- 6 beats/min (P less than 0.0025), and aortic systolic pressure fell from 151 +/- 11 to 141 +/- 9 mm Hg (0.05 less than P less than 0.10), resulting in a 16.8% reduction in the tension-time index. Stroke volume was reduced by 10% despite a 54% increase in left ventricular end-diastolic pressure, suggesting a negative inotropic effect. This was supported by a decrease in maximum extrapolated contractile element velocity from 9.10 +/- 1.05 to 6.61 +/- 65 units/sec (P less than 0.0025). Myocardial oxygen consumption was reduced from 12.0 +/- 1.4 to 9.9 +/- 1.5 ml/min/100 g tissue (P less than 0.05). Myocardial oxygen extraction was unchanged, indicating that the decrease in oxygen consumption resulted from a reduction in m...Continue Reading

Citations

Jan 1, 1981·European Journal of Drug Metabolism and Pharmacokinetics·L AllanR F Palmer
Mar 4, 1983·European Journal of Pharmacology·B T EllerB R Lucchesi
Mar 1, 1980·Xenobiotica; the Fate of Foreign Compounds in Biological Systems·A BarrowR F Palmer

Related Concepts

Metazoa
Diastolic Blood Pressure
Cardiac Output
Depression, Chemical
Canis familiaris
Dose-Response Relationship, Drug
Heart
Pulse Rate
Myocardial Contraction
Myocardium

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