Inhibited drinking and pica in rats following 2-deoxy-D-glucose.

A sequence of studies sought to determine if 2-deoxy-D-glucose (2DG) produces malaise as a side effect. Drug treatment at dosages at least as low as 250 mg/kg triggered an immediate inhibition of fluid intake. In nondeprived animals, 750 mg/kg but not lower dosages of 2DG evoked a delayed but statistically significant level of pica as measured by kaolin consumption. Twenty-four hour food deprivation failed to produce pica, and previous claims that kaolin intake is a specific index of gastrointestinal distress therefore received additional support. Thirsty rats injected with 750 mg/kg 2DG displayed a delayed pattern of pica largely similar to that previously observed with undeprived subjects; although, under optimal circumstances, significant increases in kaolin consumption may be evident as soon as one hour post-injection. In general, these data indicated that malaise may be an important influence of 2DG; but dosage and time course parameters associated with post-drug reductions in drinking suggested that a separable consummatory inhibition effect may also occur.