Effect of sustained portal-systemic shunting on glycolytic and citric-acid cycle intermediates in the rat brain.

The effect of portacaval (PC) shunting on brain glycogen, glucose, glycolytic and citric-acid cycle intermediates was analysed in rats shunted for 3, 8 and 16 weeks. Portal-systemic shunting was accompanied by a progressive fall in brain glucose which was reduced to about half of control after 16 weeks of shunting (P less than 0.05). Glycogen remained unchanged. Glucose-6-phosphate and fructose-1,6-diphosphate were significantly (P less than 0.05) increased and decreased, respectively, which may indicate some inhibition of phosphofructokinase. These changes in brain glucose content and glycolysis may be additive to any further metabolic perturbation and provide one tentative mechanism of sensitization of the brain in liver failure.