GHRELIN LEVEL CHANGES IN RATS WITH TYPE 2 DIABETES MELLITUS
Keywords:T2DM, Ghrelin, Glucose levels, STZ
Purpose: The aim of our research was to identify the ghrelin concentration in experimental animals before and after low doses of Streptozotoccin injection.
Materials and methods: Experiments were performed on male Wistar rats. Animals were divided into two groups; control and experimental group. In the control group animals had normal weight. Animals from the experimental group were divided into three subgroups, based on the rats weight: normal weight group (Group I), overweight group (Group II) and obesity group (Group III). Glucose levels were tested 4 weeks after multiple low doses of STZ injection. All rats with fasting blood glucose concentrations greater than 14 mmol/l were considered to be diabetic and were selected for further research. In all rats (control and experimental group), ghrelin levels were tested before and after multiple low doses of STZ injection.
Results: Ghrelin levels were higher in normal weight rats than in obese and overweight subjects. In the experimental group, after multiple low doses of Streptozotocin injection (30 mg/kg- twice) Ghrelin levels increased proportionately in all three groups.
Conclusion: At the beginning of our experiment, in subjects without T2DM, ghrelin levels were higher in normal weight rats than in obese and overweight subjects, but after multiple low doses of streptozotocin injection (30 mg/kg- twice), ghrelin levels increased proportionately in all three groups. As is known from recent research, ghrelin inhibits insulin secretion, and in the situation where there is an already high insulin resistance, in type 2 diabetes, ghrelin levels increase with diabetes compared to a control group, and it potentially decreases the effectiveness of endogenous insulin. It has also been observed that an increase of ghrelin is accompanied by increased glucose levels. Results of the experiment confirms ghrelin’s suppressive effect on insulin secretion.
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