Abstract
INTRODUCTION: According to the International Diabetes Federation, the number of people with diabetes mellitus may reach 700 million in 2045. Catecholamines are involved in the regulation of several kidney functions. This study investigates the effects of hyperglycemia on catecholamines' metabolism in kidney tissue from control, diabetic, and insulin-treated diabetic rats, both in vivo and in vitro. METHODS: Male Wistar-Hannover rats were randomized into: control, diabetic, and insulin-treated diabetic groups. Diabetes was induced by a single injection of streptozotocin, and diabetic treated group also received insulin. After 60 days, blood and kidney tissue from all groups were collected for catecholamines' quantification and mesangial cells culture. RESULTS: diabetic rats had lower body weight, hyperglycemia, and increase water intake and diuresis. Additionally, diabetes promoted a sharp decrease in creatinine clearance compared to control group. Regarding the whole kidney extracts, both diabetic groups (treated and non-treated) had significant reduction in norepinephrine concentration. In mesangial cell culture, catecholamines' concentration were lower in the culture medium than in the intracellular compartment for all groups. Norepinephrine, epinephrine, and dopamine medium levels were increased in the diabetic group. CONCLUSION: The major finding of the present study was that 8 weeks of diabetes induction altered the kidney catecholaminergic system in a very specific manner, once the production of catecholamines in the excised kidney tissue from diabetic rats was differentially modulated as compared with the production and secretion by cultured mesangial cells.