Serum xanthine dehydrogenase of carbon tetrachloride-induced hepatotoxicity in alloxan-diabetic rats.

Xanthine dehydrogenase activity was determined in blood serum of rats in which diabetes had been induced by alloxan administration. The results show that there is no statistical significance in the difference found for normal and diabetic rats. Alloxan produced an inhibition in the enzyme activity in animals in which a carbon tetrachloride hepatotoxicity had been induced.     

Amygdaloid kindling in alloxan-diabetic rats

Wistar rats, made diabetic by intravenous administration of alloxan, 40 mg/kg, were submitted to amygdala kindling. The EEG and behavioral responses elicited by stimulating the amygdala nuclei in these animals were compared with those observed in control rats. Alloxan-treated rats required more stimulation to kindle, had increased duration of afterdischarges (AD), presented intense interictal spiking, and exhibited greater number of wet-dog shakes than controls. Although the AD threshold was not different between control and experimental rats, the above results seem to indicate an increase in the local epileptic susceptibility represented by longer ADs. On the other hand, this increased local discharge seems to be unable to access the generalization mechanism, which can be verified by the increased kindling rate. Hyperosmolarity, pH alterations, or other generalized metabolic changes frequently associated with diabetes could be implicated in these results.     

Potentiation of the hepatotoxic responses to chemicals in alloxan-diabetic rats.

Alloxan diabetes enhances the hepatotoxic response of male rats to chloroform and 1, 1, 2-trichloroethane, but not to trichloroethylene nor 1, 1, 1-trichloroethane. Insulin treatment partially protects the animals against the alloxan-induced enhancement of chloroform hepatotoxicity. Alloxan diabetes also enhances the hepatotoxic response to galactosamine but not to beryllium nor alpha-naphthylisothiocyanate.     

Depression of estrogen-induced uterine peroxidase in alloxan-diabetic rats

The influence of alloxan diabetes on reproductive function and the estradiol-stimulated increase in uterine peroxidase was investigated. Alloxan monohydrate in a dose of 75 mg/kg body weight effectively produced permanent diabetes. In adult rats, 20 days of diabetes resulted in cessation of the estrous cycle and a significant reduction in the gain of body weight, the weights of anterior pituitary gland, ovary, uterus, the level of serum progesterone and the activity of the estradiol-stimulated uterine peroxidase (P less than 0.05). After 10 days of insulin treatment, the ovarian weight, the estrous cycle and the level of ovarian hormones were restored to normal whereas the uterine weight and the estradiol-stimulated uterine peroxidase activity were only partially recovered. Persistent depression of the uterine response in the insulin-treated diabetic rats to both endogenous and exogenous ovarian hormone stimulation suggests that the uterus was directly affected by diabetes. The direct effect of diabetes upon the uterus was further demonstrated in the ovariectomized immature rat in which diabetes depressed the stimulatory action of estradiol on both uterine weight and uterine peroxidase activity.     

Fenugreek attenuation of diabetic nephropathy in alloxan-diabetic rats

Diabetic nephropathy is a major cause of morbidity and mortality in diabetic patients. To prevent the development of this disease and to improve advanced kidney injury, effective therapies directed toward the key molecular target are required. In this paper, the efficacy of fenugreek to restore the kidney function of diabetic rats via its antioxidant and anti-inflammatory activities has been studied. Novel data showing the efficacy of fenugreek to attenuate progression of diabetic nephropathy and production of interleukin-6 (IL-6) in rats compared with a diabetic untreated group were obtained. Rats were classified into five groups; control, diabetic untreated, and three diabetic groups treated with fenugreek, rosiglitazone, and metformin. Treatment with fenugreek has been continued for 12 weeks. Fenugreek was found to significantly reduce the high levels of glucose, urea, creatinine, sodium, potassium, and IL-6 in serum compared with the diabetic untreated group. In addition, levels of malondialdehyde and IL-6 in the kidney homogenate were significantly reduced as a result of the fenugreek treatment compared with the diabetic untreated group. Moreover, concentration of GSH and the activity of both superoxide dismutase and catalase were considerably increased in the diabetic treated groups compared with the diabetic untreated group. Furthermore, glomerular mesangial expansion was reduced in the treated animal groups. These findings suggest a therapeutic potential of fenugreek against diabetic nephropathy, explain its antioxidative/anti-inflammatory properties and provide a direction for future research.     

Xanthine dehydrogenase accumulation in developing Drosophila eyes

Xanthine dehydrogenase activity is assayed by following the oxidation of pterin to isoxanthopterin by spectrofluorometry at the reaction's wavelength peaks: excitation, 344 nm; emission, 412 nm. The method is sensitive to less than 0·1 μU of activity (0·1 pmol/min) and allows the assay of Drosophila imaginal disk homogenates.While the larval eye disk contains less than 0·1 per cent of the individual's XDH, the developing eye becomes a major store, with 30 per cent of the individual's activity by the time of eye pigmentation. The data suggest a basis for the well-known non-autonomous action of the gene rosy, the structural gene for XDH: the enzyme is synthesized in an organ of primary gene expression, and transported through the haemolymph to the eye of the pupa and pharate adult.     

Malate dehydrogenase and lactate dehydrogenase in the serum of hyperthyroxinemic and hypothyroid rats]

In serum of hyperthyroxinemic and hypothyreotic rats the activities of MDH and LDH were investigated. In both groups the level of MDH was significantly elevated in comparison with control animals. The activity of LDH did not show any significant alterations.