Análise histomorfométrica renal de ratos induzidos à hiperprolactinemia tratados com melatonina

Abstract

The increase in prolactin levels causes a pathological condition called hyperprolactinemia. This condition is associated with many diseases, including chronic kidney disease (CKD), which represents the most common pituitary hypersecretion syndrome in both men and women. On the other hand, melatonin has shown the potential to prevent hepatotoxicity and nephrotoxicity, due to the role in the elimination of free radicals by melatonin (MEL). Based on this, the objective of the present work was to perform renal morphometric analysis of rats induced to hyperprolactinemia and treated with melatonin. For the work, 36 male rats were used, divided into two treatment periods: 30 and 60 days, each treatment group was subdivided into three groups: Control, DOMP (rats induced to hyperprolactinemia) and DOMP+MEL (rats induced to hyperprolactinemia and treated with melatonin). Melatonin treatment was 200μg/100g, subcutaneously (SC). The induction of hyperprolactinemia was achieved with a dose of 4mg/kg of domperidone, via SC. The results of renal histomorphometric analysis of control and treated animals over a 30-day period demonstrated that there was no significant difference in the following variables: glomerular area, glomerular capsule area, urinary space and glomerular diameter. In the analyzes of the proximal convoluted tubules (TCP), the tubule area and height of the epithelium showed an increase in those who received treatment during both periods. The distal convoluted tubules (DCT) also presented the same characteristics as the TCP. As biometric measurements, the renal weight and the weight of the animals also showed no significant differences. During the 30-day treatment period, the somatic renal index variable showed a significant difference with values of 0.29 ± 0.05 and 0.22 ± 0.04 between the control and DOMP+MEL groups, respectively. Treatment with domperidone caused histomorphometric damage in the renal parenchyma of adult rats, in animals treated in both time periods. The changes caused in the structure of the nephron, caused in the groups that used only domperidone, suggest that this treatment negatively influences renal functions, reducing renal activity and consequently homeostatic functions. Treatment with exogenous melatonin proved to be efficient in reversing the damage caused by domperidone, highlighting its renoprotective properties.