Ribose accelerates the repletion of the ATP pool during recovery from reversible ischemia of the rat myocardium.

It is a characteristic feature of the myocardium that the derangement in function [6] and the depletion of the ATP pool [1, 2, 9] that occur subsequent to oxygen deficiency persist when blood flow is restored. Of renewed interest is the inability of the heart to replenish rapidly its adenine nucleotide pool once it has been diminished during a brief period of regional ischemia [2, 9]. A hypothesis that could explain this metabolic insufficiency of the myocardium is that the biosynthesis of adenine nucleotides is very slow in the normal heart and is increased only moderately during postischemic recovery [15] so that the replenishment of adenine nucleotides is not affected appreciably. To substantiate such a hypothesis it is necessary to provide evidence that the restitution of the ATP pool can be accelerated by stimulation of this biosynthetic process. In previous studies ribose has been recognized as a substrate that enhances markedly adenine nucleotide biosynthesis in the rat heart [11, 12]. We now demonstrate that continuous i.v. infusion of ribose during recovery from a 15-min period of myocardial ischemia in rats leads to restoration of the cardiac ATP pool within 12 h, whereas 72 h are needed for ATP normalization without any intervention.