Vagotomy associated with splenectomy reduces lipid accumulation and causes kidneys histological changes in rats with hypothalamic obesity.

PURPOSE: To evaluate the influence of autonomic vagal and splenic activities on renal histomorphometric aspects in obese rats. METHODS: Thirty male Wistar rats were used, of which, 24 received subcutaneous injections of monosodium glutamate (MSG) during the first 5 days of life (4 g/kg body weight) and six control animals received injections of saline solution (CON). Five experimental groups were organized (n = 6/group): falsely-operated control (CON-FO); falsely-operated obese (MSG-FO); vagotomized obese (MSG-VAG); splenectomized obese (MSG-SPL); vagotomized and splenectomized obese (MSG-VAG-SPL). RESULTS: The MSG-FO group animals showed a significant reduction in body weight and nasal-anal length when compared to CON-FO group animals (p < 0.05). The MSG-VAG-SPL group showed significant reduced in most biometric parameters associated with obesity. Falsely-operated obese animals showed a significant reduction in renal weight, glomerular diameters, glomerular tuff and capsule areas and Bowman's space compared to CON-FO group animals (p < 0.05). There was a significant reduction in diameter, glomerular tuft and capsule areas, and Bowman's space in MSG-VAG, MSG-SPL, MSG-VAG-SPL groups when compared to the MSG-FO group. CONCLUSIONS: Vagotomy associated with splenectomy induces a reduction in the adiposity and causes histological changes in the kidney of obese rats.

Lobe variation effects of experimental diabetes and insulin replacement on rat prostate.

We investigated the impact of diabetes with simultaneous and late insulin replacement on rat prostate growth during puberty, paying special attention to different prostatic lobes. Diabetes was induced by administration of streptozotocin (STZ) in 40-day-old male Wistar rats. A subset of diabetic rats underwent simultaneous insulin replacement (3 days after STZ administration), and another subset underwent a late insulin replacement (20 days after STZ administration). The ventral, dorsolateral, and anterior prostatic lobes were weighed and processed for histological, immunohistochemical, and morphometric analyses. Both diabetic and insulin-treated animals maintained low plasma testosterone (T) concentrations, whereas dihydrotestostenore (DHT) levels were normal. Diabetic animals had a decreased gain in absolute prostatic weight when compared to age-matched controls and insulin replacement animals. However, prostatic lobe weight in the diabetic animals was ∼100% higher, even at the beginning of the experiment. Among the lobes, the anterior lobe showed the highest weight gain in diabetic and insulin replacement conditions. Epithelial cell proliferation in all lobes was significantly reduced in diabetic animals and significantly increased in insulin replacement animals, although apoptosis was unaltered. In conclusion, diabetes diminishes, but does not abolish, prostate growth during puberty. Even late insulin administration reduces the adverse effects of this disease on the prostate. In a scenario with both low insulin and T levels, DHT and other factors may play an important role in pubertal prostate growth. The adverse effects of diabetes on the rat prostate show a variation in lobe response, suggesting that diabetes may affect human prostate zones differently.

Effects of altered epididymal sperm transit time on sperm quality.

The epididymal sperm transit time seems to have an important role in the process of sperm maturation, and it seems that alterations to the transit can harm the process. The aim of the present work was to evaluate the influence of altered sperm transit time through the epididymis on sperm parameters and fertility of rats, as well as the role of testosterone in the alterations. Sprague-Dawley adult male rats were randomly assigned to four different groups and were treated for 12 days: (i) 10 microg/rat/day DES, to accelerate the transit; (ii) 6.25 mg/kg/day guanethidine sulphate, to delay the transit; (iii) same treatment as group 1, plus androgen supplementation; (iv) control animals received the vehicles. Guanethidine treatment delayed the sperm transit time through the epididymal cauda, provoking increased sperm reserves in this region. Animals exposed to DES showed an acceleration of sperm transit time in the epididymis, and consequently decreased sperm density in both epididymal regions, the caput-corpus and cauda, and diminished sperm motility. In both cases sperm production was not altered. Testosterone supplementation was able to restore the transit time to values close to normality, as they were higher than in the control rats. The same occurred in relation to sperm motility. Rats exposed to DES presented lower fertility after in utero artificial insemination using sperm collected from the proximal cauda epididymis. Therefore, it was concluded that the acceleration of rat sperm transit time appeared to harm normal sperm maturation, thus decreasing sperm quality and fertility capacity, in an androgen-dependent way.