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Phosphate loading prevents the decrease in ATP and increase in food intake produced by 2,5-anhydro-D-mannitol.

Abstract

The fructose analogue 2,5-anhydro-D-mannitol (2,5-AM) triggers feeding in rats apparently by its action in the liver. In vivo phosphorylation of this analogue decreases hepatic inorganic phosphate and ATP by trapping of phosphate in the mono- and diphosphorylated forms of 2,5-AM. To determine whether hepatic phosphate depletion and decreased ATP are involved in the eating response to 2,5-AM, rats were treated with excess sodium phosphate before injection of 2,5-AM. Phosphate loading prevented both the increase in food intake and the decrease in liver ATP, without affecting the changes seen in plasma fuels produced by 2,5-AM treatment. Phosphate loading did not influence water intake or eating elicited by insulin or 2-deoxy-D-glucose, indicating that the effect on 2,5-AM-induced eating was behaviorally specific and not due to malaise. These data suggest that 2,5-AM elicits eating by trapping phosphate and reducing ATP in liver.

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BibTeXRIS

N E Rawson, M I Friedman. 1994. Phosphate loading prevents the decrease in ATP and increase in food intake produced by 2,5-anhydro-D-mannitol.. https://doi.org/10.1152/ajpregu.1994.266.6.r1792

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