Glutamine utilization in resting and stimulated platelets.
Exogenous glutamine was metabolized by platelets to glutamate, aspartate, and CO2; whereas no lactate was formed. The amount of aspartate and CO2 produced from glutamine was reduced by the presence of glucose. On the other hand the rate of oxidation of glucose was reduced by the presence of glutamine. The potential energetic value of glutamine was lower than that of glucose, but the amino acid appeared to be a preferential respiratory substrate. The energy provision from glutamine also plays a role in the process of platelet activation, known to require an extra supply of ATP, since thrombin increased the rate of glutamine utilization in platelets. Upon cell activation an increase in aspartate and CO2 formation was observed and the stimulatory effect on glutamine oxidation by thrombin was also maintained in the presence of glucose.
Vasta
V
V
Dipartimento di Scienze Biochimiche, Università di Firenze, Italy.
Meacci
E
E
Farnararo
M
M
Bruni
P
P
D001224:Aspartic Acid / Q000378:metabolism; D001792:Blood Platelets / Q000378:metabolism*; D002245:Carbon Dioxide / Q000378:metabolism; D005947:Glucose / Q000378:metabolism; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid; D005973:Glutamine / Q000378:metabolism*; D006801:Humans; D010084:Oxidation-Reduction; D015539:Platelet Activation; D013917:Thrombin / Q000494:pharmacology
D005971:Glutamates; D005973:Glutamine; D002245:Carbon Dioxide; D001224:Aspartic Acid; D018698:Glutamic Acid; D013917:Thrombin; D005947:Glucose