Energy substrate metabolism in fresh and stored human platelets.
The latent capacity of human platelets for oxidizing several important energy-yielding substrates has been revealed by hypoosmolaric incubation conditions. The data show that the human platelet has a considerable capacity to oxidize both glucose and long-chain fatty acids. Long-chain fatty acids appear to rank favorably with glucose as a potential energy substrate. In a number of mammalian tissues, (-)-carnitine serves to regulate the rate at which long-chain fatty acids are oxidized. Evidence was obtained which suggests that (-)-carnitine functions in a similar role in the platelet. After storage of human platelets at 4 degrees C for 24 hr, the oxidative capacity for glucose was reduced by approximately 25% and for long-chain fatty acids by almost 50%. Investigation of the component parts of the metabolic pathways indicated that a marked decrease in the capacity of the Krebs cycle could be responsible for the decrement in energy substrate oxidation.
D000255:Adenosine Triphosphate / Q000494:pharmacology; D001792:Blood Platelets / Q000378:metabolism*; D001793:Blood Preservation; D002247:Carbon Isotopes; D002331:Carnitine / Q000494:pharmacology; D002855:Chromatography, Thin Layer; D002952:Citric Acid Cycle; D005227:Fatty Acids / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D006801:Humans; D066298:In Vitro Techniques; D009829:Oleic Acids / Q000378:metabolism; D009994:Osmolar Concentration; D010084:Oxidation-Reduction; D011773:Pyruvates / Q000378:metabolism; D013386:Succinates / Q000378:metabolism; D013696:Temperature; D013997:Time Factors
D002247:Carbon Isotopes; D005227:Fatty Acids; D009829:Oleic Acids; D011773:Pyruvates; D013386:Succinates; D000255:Adenosine Triphosphate; D005947:Glucose; D002331:Carnitine