Bioenergetics in clinical medicine XV. Inhibition of coenzyme Q10-enzymes by clinically used adrenergic blockers of beta-receptors.
Adrenergic blockers for beta-receptors were studied for inhibition of mitochrondrial CoQ10-enzymes. These enzymes are indispensable for the bioenegetics of the myocardium. Propranolol is frequently used to treat hypertension; in some patients, it depresses myocardial function as an adverse reaction. This side effect may be related to the inhibition by propranolol of CoQ10-enzymes of the myocardium. Timolol showed negligible inhibition of the CoQ10-enzyme, NADH-oxidase. Metoprolol was less inhibitory than propranolol. Five alprenolols showed inhibition which approached that of propranolol. The 1-isomer of alprenolol showed weak inhibition of another CoQ10-enzyme, succinoxidase, but the other beta-blockers were essentially non-inhibitory to this enzyme. The drug of choice is timolol, based on negligible inhibition of these bioenergetic enzymes of the heart, which correlates with its pharmacologically low cardiac depressant effects.
D000319:Adrenergic beta-Antagonists / Q000494:pharmacology*; D000526:Alprenolol / Q000031:analogs & derivatives / Q000494:pharmacology; D009247:NADH, NADPH Oxidoreductases / Q000037:antagonists & inhibitors; D011433:Propranolol / Q000031:analogs & derivatives / Q000494:pharmacology; D013237:Stereoisomerism; D013999:Timolol / Q000494:pharmacology; D014451:Ubiquinone / Q000037:antagonists & inhibitors*
D000319:Adrenergic beta-Antagonists; D014451:Ubiquinone; D013999:Timolol; D000526:Alprenolol; D011433:Propranolol; D009247:NADH, NADPH Oxidoreductases