Evaluation of certain Criteria in the blood and tissues of zinc deficient rats and zinc supplemented ones

Thirty weanling male albino rats weighting 70 - 80 g were divided into 3 equal groups. These groups were fed on three semi purified diets differ in their contents of zinc / kg diet for 6 weeks as follows : Zn-adequate diet (Zn = 35 ppm) for group (A), Zn-deficient diet (Zn = 3 ppm) for group (B) and Zn- sufficient diet (Zn=84 ppm) for group (C) supplemented as 3 ppm Zn for 4 weeks then 81 ppm Zn for 2 weeks. The aim of this work is to evaluate selected biochemical determinate in the blood and tissues of Zn-deficient rats and after Zn supplementation to help in diagnosis between them and those evolved in the case of protein-calorie malnutrition which looks like Zn-deficiency to some extent in some manifestations. The results obtained revealed that Zn-deficiency led to significant (P<0.05) decline of Zn concentrations in serum, liver, lung and testis as compared to Zn-sufficient ones. Also, in Zn-deficient animals, serum total thyroxine (T4), triiodothyronine (T3) and testosterone levels were declined compared with their levels in Zn-sufficient rats. On the contrast, the concentrations of total cholesterol (T.Chol), high density lipoprotein (HDL), low density lipoprotein (LDL) and triglycerides (TG) in sera of Zn-deficient animals were significantly higher than those recorded in Zn-sufficient rats. The activities of cytochrome P450 reductase and microsomal NADPH reductase were decreased (P<0.05) in liver homogenates, while they were increased (P<0.05) in lung and testis derived from Zn-deficient rats than in normal Zn-adequate ones. Whereas, aminopyrine demethylase exhibited significant (P<0.05) reduction in its activity in all tissues studied herein than their corresponding activities in the same tissue removed from Zn-sufficient rats. On the other hand, zinc supplementation to the diet seemed to have beneficial effects and it was able to restore the levels of the above mentioned determinants almost close or sometimes above the normal levels in short time. Hence, this study provides evidence about the importance of zinc supplementation to the diets contain low zinc and considered as a remedy of zinc deficiency