Ribose Prevents the Propranolol-Induced Reduction of Myocardial Adenine Nucleotide Biosynthesis
Blockade of myocardial ß-adrenergic receptors with high doses of propranolol has been shown to be accompanied by a marked reduction in cardiac adenine nucleotide biosynthesis1. It was therefore of interest to examine whether this reduction may be prevented by another intervention in adenine nucleotide biosynthesis. An experimental approach which seemed to be most promising for reaching that goal is the administration of ribose. This pentose which bypasses the hexose monophosphate shunt has been demonstrated to elevate the available pool of 5-phosphoribosyl-1-pyrophosphate and to stimulate adenine nucleotide biosynthesis in the normal rat heart in vivo2. Furthermore, ribose potentiates the enhancement of myocardial adenine nucleotide biosynthesis during development of cardiac hypertrophy3 and during recovery from oxygen deficiency4. Ribose was therefore administered as continuous i.v. infusion in rats that were treated with a high dose of propranolol, and myocardial adenine nucleotide biosynthesis was then determined.
KeywordsAdenine Nucleotide Left Coronary Artery Aortic Constriction Ventricular Free Wall Nucleotide Biosynthesis
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