Alternative Fuels for Platelet Storage: A Metabolic Study

We have studied the metabolism of platelets in vitro using washed platelets. Oxygen uptake and fuel utilization were measured. It was found that glucose is never oxidized to any significant extent and is always converted to lactate, regardless of oxygen availability. Oxidative metabolism fuels 70-100% of the ATP turnover, and oxygen uptake is the same whether the platelet is consuming glucose, acetate or only an unidentified endogenous fuel. When acetate is the added fuel, no endogenous fuel is oxidized, whereas the addition of glucose results in sparing of only 8% of endogenous fuel. Preliminary storage experiments using plasma-free media show that an acetate-containing buffered salt solution provided excellent storage conditions and that a medium without any exogenous fuel is better than one containing glucose. Thus we conclude that a successful storage medium should contain minimal amounts of glucose, and an oxidizable fuel such as acetate, in order to supplement the endogenous one.