1110 HYPERTRIGLYCERIDEMIA INDUCED BY ZINC DEFICIENCY

Serum lipid abnormalities have been found to be associated with zinc deficiency (Zn-). We observed that serum triglycerides (TG) responded rapidly to alterations in zinc nutritional status. After 7 days on Zn- diet (Zn 1 ppm), TG were increased by 200%, whereas in rats fed a control (C) diet (100 ppm) no changes in TG levels were recorded. By continuing the Zn- diet the TG increased gradually to 600% of the initial value after day 28, when TG leveled off. Thus, the elevation in TG preceded clinical signs of Zn-, and the elevation in TG is higher in the more severely deficient rats. Zn- rats fed the C diet or a Zn enriched (Zn +) diet (500 ppm) were repleted with Zn rapidly and TG decreased to normal values. Thus, hypertriglyceridemia (HTG) of Zn- is reversible when dietary Zn is increased and body stores of Zn are repleted. The HTG may be related to the decrease in post heparin plasma lipoprotein lipase between Zn- (370 ± 98 DPM glycerol release/mg protein/30 min) and C (510 ± 124). To test the hypothesis that Zn- rats have a higher level of endogenous lipid production, in vitro liver metabolism experiments were undertaken. Liver slices were incubated with (14C) glucose or (14C) palmitate and their utilization for TG synthesis and 14C02 production was measured. The results showed higher incorporation into TG in Zn- rats which may be due to an abnormality in carbohydrate metabolism.