Substrate utilization by rat stomach in vivo. Arteriovenous differences for glucose, lactate, ketone bodies, fatty acids and glycerol under control and acid-secreting conditions.

Arteriovenous differences for several potential metabolic substrates were measured across the fundic wall of the stomach of rats that had been starved overnight. There was an uptake of glucose and D-3-hydroxybutyrate, but no significant arteriovenous differences for acetoacetate, pyruvate, non-esterified fatty acids and glycerol were apparent. Lactate output represented a substantial fraction of glucose uptake when the arterial lactate concentration was within the resting physiological range, but when the arterial lactate concentration was above 1.3 mM, lactate was taken up by the stomach. Stimulation of acid secretion by pentagastrin did not affect the value of arteriovenous differences. Thus blood flow to the fundic mucosa and substrate metabolism may be similarly enhanced by pentagastrin. It is concluded that metabolism of glucose and D-3-hydroxybutyrate, and to a lesser extent of glutamine and branched-chain amino acids [Anderson & Hanson (1983) Biochem. J. 210, 451-455], could supply energy to power acid secretion.