Effects of free radical scavengers on the metabolic control of streptozotocin induced diabetes in rats

The aim of this study was to investigate the effect of antioxidant vitamin C and E either alone or in combination and also the effect of melatonin on the blood glucose, insulin, C peptide and lipids in streptozotocin diabetic rats. Sixty male albino rats were divided into six equal groups; one served as a control, rats in the other groups were rendered diabetic by a single intraperitoneal injection of 30 mg/kg body weight streptozotocin [STZ] and were divided into five equal groups, one remained diabetic without antioxidants, while the other four groups were given daily an oral supplementation of vitamin C, vitamin E, combined treatment of vitamin C and E and melatonin, respectively. The current study implied that melatonin and a combination therapy of vitamin C and E induced the most beneficial effect in STZ diabetic rats, especially in a pattern of changes in the total cholesterol and lipoprotein metabolism that are related to the increased risk of atherosclerosis

Influence of cigarette smoking and diabetes on fertility and spermatogenesis of male rats: hormonal, histological and histochemical studies

This study was designed to evaluate the effect of cigarette smoking, diabetes mellitus and their combination on serum levels of total testosterone, follicle stimulating hormone [FSH], luteinizing hormone [LH], percentage of morphologically abnormal sperms, testicular weight, histology and histochemistry. This study divided 40 male rats into 4 equal groups: Group I served as controls, group II was exposed to the smoke of 20 cigarettes/day, group III was rendered diabetic by a single intraperitoneal injection of 40 mg/kg body weight streptozotocin, while group IV was rendered diabetic and subjected to cigarette smoking. The experimental work continued for 65 days. The results showed that either cigarette smoking or diabetes produced a significant decrease in serum levels of FSH, LH, testosterone, diameters of seminiferous tubules and thickness of the spermatogenic cells versus the control group

Effects of acute exercise and exercise training on thyroid functions in rats

This study was designed to elucidate the effects of swim exercise on serum thyroid stimulating hormone [TSH], thyroxine [T4] and triiodothyronine [T3] levels in male rats. Thirty animals were included in the study and divided into three groups: Group I served as control and left sedentary in their cages, group II included rats exercised for a single bout of 30 minutes [acute exercise] and group III included rats exposed to daily exercise bouts of 30 minutes for 21 consecutive days [chronic exercise]. Serum TSH, T4 and T3 were determined by radioimmunoassay [RTA] and the values were compared with the control group. The results showed that T4 and T3 levels were significantly lowered in acute swim exercise, but TSH was slightly changed. On the other hand, chronic swim exercise elicited a significant rise in serum T4 and significant reduction in T3 concentrations, while TSH serum level increased insignificantly

Markers of antioxidative capacity [superoxide dismutase, catalase, glutathione peroxidase and glutathione reductase] in female rats: correlation with cigarette smoke air pollution and estrogen deficiency

This study was designed to evaluate the effect of cigarette smoke exposure and its cessation on the activities of superoxide dismutase [SOD], catalase [CAT], glutathione peroxidase [GPx] and glutathione reductase [GR] of intact and ovariectomized rats as biochemical markers of antioxidant status. Forty female adult rats were divided into four equal groups. Activities of SOD, CAT and GPx increased significantly in intact rats exposed to cigarette smoke and ovariectomized unexposed rats, while GR activity decreased significantly compared with intact unexposed ones. Activities of SOD, CAT, GPx and GR decreased significantly in cigarette smoke exposed ovariectomized rats compared with ovariectomized unexposed ones. Adaptation took place in the activities of SOD, CAT, GPx and GR of intact rats on smoking cessation, while it occurred only in GPx activity of the ovariectomized ones

Serum thyroglobulin, catecholamines and phospholipids in violent asphyxia, an experimental study on rats

Elevation of serum thyroglobulin [Tg], catecholamines, and phospholipids concentrations in the blood are regarded as vital reactions in asphyxial deaths which leave few or no external signs in the body. In this study, these vital reactions were tested under strict experimental conditions, employing rapid asphyxia. Forty adult albino rats of both sexes, of average weight 200 g., were used. Ten animals were used as a control group, the remaining animals were anaesthetized and strangled with a rope, 2 mm thick, tightened around the neck. At the moment of death, which was determined when the heart beat had faded about 3-4 minutes from the start of strangulation, blood samples were taken, centrifuged, and the serum thyroglobulin, catecholamines, and phospholipids were measured. The lungs were also investigated histologically to study the general microscopic structure of the asphyxiated lung. The results showed a significant increase in the concentration of thyroglobulin as compared to control [Tg = 14.44 ng/ml versus 2.97 ng/ml, P < 0.001]. The mean serum adrenaline [A] and noradrenaline [NA] concentrations were significantly higher in strangulation group as compared to control, [A = 8.07 ng/ml. vs. 3.18 ng/ml, P < 0.001]. The mean serum phospholipids concentration in the strangulated rats was 1.76 g/L versus 1.03 g/L in the controls, P < 0.001. Concerning the histological investigation, the lung showed emphysematous changes with collapse and tiny haemorrhages. The alveoli were distended and ruptured. The alveolar epithelium was thin, desquamated and over folded with increase of mucoid secretion. High levels of thyroglobulin, catecholamines, and phospholipids in the blood upon suffocation could thus be taken as indicators of hypoxia, and therefore can be included in the diagnosis of mechanical asphyxia