TIME-DEPENDENT CHANGES IN PLASMA GHRELIN AND ANGIOTENSIN II LEVELS IN THE DIABETIC NEPHROPATHY MODEL

Ghrelin is an appetite-enhancing anabolic hormone secreted from the stomach. Angiotensin II maintains sodium and potassium levels in body fluids and plays a very important role in the regulation of arterial blood pressure. Although their relationship with Type 2 diabetes and complications have been reported, their role in diabetic nephropathy is not fully understood. We investigated time dependent possible changes in plasma ghrelin and angiotensin II levels during the development and progression of diabetic nephropathy in experimental diabetic rat model. Adult 63 male Wistar Albino rats were randomly divided into 9 groups as 4 control (C1-C4), 4 diabetic (D1-D4) and one treatment (T) group. Group D1, sacrificed by cardiac puncture one week after diabetes, group D2 three weeks later, group D3 six weeks later, and groups D4 and T eight weeks later. Antidiabetic treatment was not administered to the D1-D4 group diabetic rats. Group T diabetic rats were treated with antidiabetic metformin (100 mg / kg / day) for 8 weeks. A single dose of 35 mg / kg intraperitoneal streptozotocin was administered to the rats to induce diabetes. Significant differences were found between the D4 and C4 groups in body weight, plasma glucose, ghrelin and angiotensin II, serum and urine creatinine levels. While there was a linear (positive) relationship between plasma ghrelin levels of all rats and urinary creatinine and creatinine clearance and body weight, negative correlations were found between plasma ghrelin and angiotensin II levels and fasting blood glucose levels of all rats. During the progression of diabetes and the development of diabetes-related nephropathy, plasma angiotensin and serum creatinine levels increased, while plasma ghrelin levels decreased over time. Therefore, it was concluded that changes in plasma ghrelin and angiotensin II levels in diabetic rats may be associated with the pathogenesis of diabetic nephropathy.