Prophylactic and protective effect of L-thyroxine on hepato-renal dysfunction induced by amika.cin and potassium dichromate

The present study was concerned with amikacin's hepatorenal hazards on certain kidney and liver tissue enzymes in normal rats as well as rats subjected to potassium dichromate induced hepatorenal toxicity. Minimizing the undue effects of both amikacin and potassium dichromate by either concomitant or pre-administration of L-thyroxine was also undertaken. Specific enzyme activity of N-acetyl-beta-D- glucosaminidase, NAG [as a marker of lysosomal enzyme], Na-K- ATPase [as a marker of basolateral membrane enzyme] and glucosed-6-phosphatase, G-6-Pase [as a marker of endoplasmic reticulum] as well as liver 5-nucleotidase specific enzyme activity were measured. The association of potassium dichromate, amikacin or both with the membrane binding caused increased lysosomal hydrolase specific enzyme activity extracted from the liver and kidney tissues, reduction of Na- K-ATPase, G-6-Pase and liver 5-nucleotidase activities, membrane damage in renal tubule of the rats as well as the induction of ultrastructural alterations of the liver. Thyroid hormone had an important stimulatory action on the plasma membrane pump that maintained cellular constancy of sodium and potassium. The recorded data may suggest that L- thyroxine administration may enable the cell to resist liver and kidney injury

Purification and partial characterization of three dipeptidases from rat liver

Three dipeptidases namely; Leu-Leu dipeptidase [LLD], Leu-gly dipeptidase [LGD] and Ala-gly dipeptidase [AGD] from rat liver were purified using L. Leu-Leu, L, Leu-gly and L.Ala-gly as substrates. The adopted purification techniques included treatment with n-butanol, acetone precipitation and drying, ammonium sulphate fractionation, DEAE-cellulose chromatography, second acetone precipitation and sephadex G-200 gel filtration. Performance of kinetic studies proved that the enzyme preparation acting on L. Ala-gly as substrate exhibited a kinetic behavior different from those acting on L. Leu-Leu and L-Leu-gly dipeptides. The data proved that LLD and LGD displayed similar behaviour with respect to activation with Mn[2+], the incidence of positive cooperativity and pH optima. However, discrepances in behaviour were indicated with respect to Km [10.0 x 10[-3] M and 8.7 x 10[-3] M for LLD and LGD respectively], pH end thermal stability. Addition of activators and inhibitors proved that the separated enzymes were metalloenzymes

Erythrocyte transketolase activity as a function of vitamin B1 after prolonged oral contraceptive administration under different vitamin B1 nutritional status

The present investigation is concerned with studying the effect of feeding adult female rats, standard synthetic diet, diets [deprived, deficient and supplemented] with high dose of vitamin B1 on vitamin B1 functional activity during prolonged administration of an oral contraceptive [O.C] [Containing 0.035 mg ethinyl estradiol and 0.5 mg norethindrone]. The experiment lasted for 165 days. Blood samples were withdrawn after 15, 45, 75, 105, 135 and 165 days from O.C administration, for the determination of vitamin B1 level by a functional test, i.e. erythrocyte transketolase [ETK] basal activity and after in-vitro thiamin pyrophosphate addition [TPP]. Results were discussed. It is proved that a proper high dose of vitamin B1 should be given during prolonged oral contraceptive administration

Effect of STZ-induced hyperglycemia on plasma TSH, T3 and T4 levels

STZ hyperglycemia was characterized by two phases; namely, first grade hyperglycemia, where mild elevation in the blood sugar level was indicated, and a second grade accompanied by a well marked hyperglycemia. Determination of plasma hormonal levels of TSH, T3 and T4, by RIA, proved the incidence of variable fluctuations. The results obtained were statistically analyzed and discussed