LIPID-ZINC INTERACTION - ITS EFFECT ON THE TESTES OF MICE

Lipid-Zn interaction in the testes of mice was studied by feeding them low-fat (30 g maize oil/kg; group LFZD) and high-fat (90 g maize oil/ kg; group HFZD) Zn-deficient diets for 6 weeks. The results were compa red with those of corresponding Zn-supplemented-diet-fed controls (gro ups LFZS and HFZS). The integument-related Zn-deficiency symptoms appe ared in group HFZD and not in group LFZD mice despite lack of Zn in th eir ration and an equal level of Zn in their blood serum. The feed int ake, gain in body weight and testes weight of the LFZD group were comp arable with those of the LFZS and HFZS groups (P > 0.05) but were high er than those of the group HFZD (P < 0.05). The testes of group HFZD d isplayed necrotic changes marked by the presence of giant cells, lower RNA, DNA and protein concentrations and higher phospholipid and chole sterol levels than those of mice in the LFZD group. The concentrations of these fractions were not significantly different between LFZD and HFZS. The results do not support the hypothesis that Zn is essential e ither for testicular function or for nucleic acid and protein synthesi s in animals fed on a low-fat diet; however, it appears to be essentia l for animals fed on a high-fat diet. The changes observed in the test es of the HFZD animals suggest the excess intake of fat as their cause in Zn-deficient animals.