Role of zinc in regulating the testicular function. Part 3. Histopathological changes induced by dietary zinc deficiency in testes of male albino rats.

Zinc deficiency affects the testicular tissues adversely. The testes of zinc-deficient rats showed variable degrees of degeneration compared to both control and zinc-supplemented ones. Initially, there was an early pronounced spermatic arrest followed by a series of degeneration of the cellular layers constituting the seminiferous tubules in the zinc-deficient rats. Degenerative changes were additionally demonstrated in the interstitial tissue cells of the zinc-deficient rats. These histopathological observations in testes of zinc-deficient rats run in parallel provide an additional support to our previous publications in which we recorded a significant reduction in both serum and testicular levels of testosterone in the same group of animals, since spermatogenesis in rodents appeared to depend primarily on testosterone level.

Role of zinc in regulating the testicular function. Part 1. Effect of dietary zinc deficiency on serum levels of gonadotropins, prolactin and testosterone in male albino rats.

Hypogonadism is a major manifestation of zinc deficiency in both humans and animals. In this study, we try to elucidate the main role of zinc in regulating the testicular function. Ninety male weanling albino rats were divided into three groups: control, zinc-deficient (ZD), and zinc-supplemented (ZS) groups. Six rats from each group were sacrificed every two weeks over a total period of ten weeks. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL) and testosterone (T) were estimated by radioimmunoassay technique. Serum zinc concentrations were also determined. Data revealed that serum zinc concentrations were significantly low in ZD group compared to both control and ZS groups. Normal FSH and LH but low PRL and T levels were demonstrated in sera of ZD group compared to both control and ZS groups. We came to the following conclusions: zinc deficiency has no effect on the pituitary gonadotropin output. Zinc deficiency affects the testicular function either directly through its effect on the testicular steroidogenesis and/or indirectly through its effect on the pituitary synthesis and/or secretion of PRL.

Role of zinc in regulating the testicular function. Part 2. Effect of dietary zinc deficiency on gonadotropins, prolactin and testosterone levels as well as 3 beta-hydroxysteroid dehydrogenase activity in testes of male albino rats.

Induced zinc deficiency in male albino rats caused a great reduction in the testicular levels of testosterone as compared to control and zinc-supplemented (ZS) rats. Estimation of the testicular levels of follicle-stimulating hormone, luteinizing hormone and prolactin (PRL) in the zinc-deficient (ZD) rats showed higher levels in comparison with both control and zinc-supplemented rats. However, the increase in PRL levels was statistically insignificant. A great reduction in the activity of 3 beta-hydroxysteroid dehydrogenase, an important enzyme involved in testosterone biosynthesis, was demonstrated histochemically in the testes of ZD rats as compared to both control and ZS ones. These results reflect a direct action of zinc deficiency on the testicular steroidogenesis and strongly support the idea that the hypogonadal state associated with zinc deficiency results mainly from some alteration in the testicular steroidogenesis or in other words Leydig cell failure.

Quantitative determination of small amounts of L-penicillamine in D-penicillamine after desulfurization with Raney nickel.

Commercially available D-penicillamine is desulfurized with Raney nickel at room temperature in aqueous solution. L-Valine derived from contaminating L-penicillamine is determined colorimetrically by the amino acid oxidase/peroxidase reaction, using 2,2'-azino-di-[3-ethyl-benz-thiazoline-sulfonate(6)] (ABTS). The procedure assures the quantitation of L-penicillamine contaminating D-penicillamine down to the level of 0.1%.

Biochemical studies on Egyptian buffalo meat Part 1. Determination of phosphorus, calcium and magnesium.

The effect of age, sex, season and cut on the phosphorus, calcium and magnesium contents of buffalo meat was studied in 128 samples. Statistical analysis for the data showed significant difference to 0.01 level for phosphorus in relation to sex and in dry season in relation to sex. There is also significant difference for both calcium and magnesium in relation to season and also in case of both male and female in relation to season. At 0.05 level, phosphorus shows a significant difference in green season in relation to sex and at 0.1 level in relation to season.

Biochemical studied on Egyptian buffalo meat. Part 2. Determination of iron, zinc and copper.

A total of 128 samples of Egyptian buffalo meat were collected from animals differing in age, sex, season and cuts. Their samples were analysed for iron, zinc and copper contents. Statistical analysis of the data obtained shows, that zinc and copper differ significantly at 0.01 level in relation to cut variation. In case of female, they differ also at the same level in relation to season. Zinc differes significantly at 0.01 level seasonally and in male in relation to season. On the other hand copper differs significantly at 0.05 level for green season in relation to sex. Iron and copper show significant differences at 0.1 level due to sex and in dry season in relation to sex, respectively.

Biochemical studies on Egyptian buffalo meat. Part 3. Determination of sodium, potassium and chloride.

Sodium, potassium and chloride contents fo buffalo meat were studied in 128 samples. Statistical analysis for the data obtained show significant difference at 0.01 level for sodium, potassium, and chloride in relation to season, and in female in relation to season. Sodium and potassium differs significantly at 0.01 level in male animals in relation to season, and chloride differs at this level due to green season in relation to sex. At 0.05 level sodium shows a significant difference in cut while chloride shows a variation at this level due to dry season in relation to sex.

A study on fungal radioresistance and sensitivity.

Lower doses of gamma and X-rays (5 and 1 Krad, respectively) stimulated the spore germination and growth of 7 tested fungi. Higher doses (500 and 100 Krad, respectively) revealed that Epicoccum nigrum was the most radioresistant, while Alternaria humicola, Stemphylium verruculosum, Rhizopus nigricans, and Cladosporium herbarum were of moderate resistance. Aspergillus niger and Penicillium oxalicum were the most radiosensitive. Protein and polysaccharide synthesis were inhibited in the mycelium developed from irradiated spores; the inhibition was a function of dose. Study of the different factors (morphological, biological, and biochemical) indicates that variability in fungal resistance to ionizing radiation is, most probably, an inherent character, connected with mycelial water content and the natural production of a chemical substance(s) that acts as a radioprotector(s).

Determinations of pH, moisture, carbohydrates and ash of Egyptian buffalo meat.

A total of 128 samples of Egyptian buffalo meat was analysed for its pH value, moisture, carbohydrates and ash contents. Statistical analysis of the data obtained shows significant difference at 0.01 level for moisture in relation to sex and cut (abdomen and thigh, respectively). There is also significant difference at 0.05 level for moisture in dry season in relation to sex and for ash in relation to cut. At 0.1 level moisture shows a significant difference in relation to season, female in relation to season and green season in relation to sex. Ash also shows a significant difference at 0.1 level in female in relation to season.

Protein, amino acid contents and protein efficiency ratio of Egyptian buffalo meat under different biological conditions.

The effect of age, sex, season and cut variations on the protein, amino acids contents and protein efficiency ratio (P.E.R.) of Egyptian Buffalo meat was studied in 128 samples. Statistical analysis for the data obtained showed significant difference at 0.01 level for protein in relation to cut (abdomen and thigh, respectively), male in relation to season and dry season in relation to sex. There is also significant difference at 0.05 level in case of green season in relation to sex. Protein shows a significant difference at 0.1 level due to sex variation. There is a difference in the amino acids content of young and old animals during dry season in both cuts. Young animals show higher values than old ones in most of the amino acids investigated. There is also an obvious difference in the amino acids during green season between male and female animals, and also between both cuts. P.E.R. of Egyptian Buffalo meat as 10% protein level ranges between 3.02 and 2.35 according to seasonal, cut and age variations.