Prednisona modifica pressão arterial sistólica e morfologia renal de ratos normotensos

Abstract

Glucocorticoids are one of the classes of drugs most used as anti-inflammatory therapies, depending on their effectiveness. However, these agents produce adverse effects, including the development of high blood pressure. Among glucocorticoids, prednisone is an intermediate potency drug, widely used in clinical practice. The aim of this study was to evaluate the effect of prolonged use of prednisone on systolic blood pressure, renal function and histology in normotensive rats. Animals weighing between 280-320 g were randomly divided into two experimental groups: Control (treated with vehicle, Syrspend) and PRD (treated with prednisone 5 mg / kg / day). The treatment was carried out daily by intragastric route (gavage) for 17 days, and blood pressure was measured before and after treatment. On the 18th day, 24- hour urine was collected and measurements of water consumption, feed and urinary flow were carried out, and then used for analysis of microalbuminuria, creatinine and urea, the last two of which were also measured in serum. The kidneys were collected and weighed to obtain their relative weight and subsequently cut sagittally for histological procedures. Statistical analysis was determined by Student's t test and p values <0.05 were considered statistically significant. It was observed that treatment with prednisone increased the levels of systolic blood pressure (mmHg), with no change in the control group (154 ± 4.8 vs. 136 ± 1.8, respectively). Histological analysis showed a significant decrease in the internal diameter of the glomeruli in the PRD group (p = 0.0096 vs. Control). Regarding the parameters of relative kidney weight, feed intake, water intake, urine flow, urine chemical analysis, microalbuminuria, serum and urine urea, serum and urine creatinine and their clearance there were no significant differences between groups, indicating that the renal function was not compromised after treatment with prednisone at the established dosage and study time. It was concluded that treatment with prednisone for 17 days, at a dosage of 5 mg / kg, changed the systolic blood pressure of Wistar rats and led to a significant decrease in the renal glomerular tuff, without directly interfering with renal function.