Galanin Antagonists And The Impact Of Exercise On Fat Cell Glucose Transporter Type 2 Diabetic Rats

Objective: To explore the effect of increase in Galanin release induced by exercise on on adipocyte glucose transportation protein 4 in the type 2 diabetic rats and its possible mechanism.Method: Female Sprague-Dawley rats were used to this experiment After fed with high-fat diet for 8 week,rats were subjected to establish 2 type diabetic model by injection of streptozotocin (30mg/kg) one time. When the models of diabetic rats were formed, the diabetic rats were randomly divided into four groups: rest control group and exercise control group were injected by saline into the abdominal cavity; rest drug and exercise drug groups by galantide,a galanin antagonist. The rats of both exercise groups swam in advance for three days, 15, 30, 50 minutes respectively; then swam formally for 10 day, 60 min/d; We measured the insulin plasma level in fasting rat by radioimmunoassay and glucose plasma level by fast plasma glucose instrumental,tested the glucose transportation protein 4 level in adipocyte cell membrane by Western blot method. And investigated insulin sensitivity of the four group rats by the euglycemic clamp, measured the insulin sensitive indexes by divided the product of the plasma insulin and the plasma glucose in fasting rat by 22.5 or calculated the natural logarithm of the product reciprocal.Results: (1) Plasma insulin levels of fasting rats in the rest drug and exercise drug groups have significantly increased after the experiment than the before(P<0.001). Compared to the rest control group, insulin levels of fasting rats after the experiment in the rest drug group have extremely remarkably increases (P<0.001). Insulin levels of fasting rats after the experiment in exercise drug group have extremely remarkably increases compared with rest control group (P<0.001). Insulin levels of fasting rats after the experiment in exercise drug group have extremely remarkably increases compared with rest exercise control group(P<0.001). Insulin levels of fasting rats after the experiment in rest drug group have extremely remarkably increases compared with rest control group(P<0.001).(2) The nember of Glut4 on adipocyte plasma membrane in exercise control group significantly increases as compared with rest control group (P<0.05) . The nember of Glut4 on adipocyte plasma membrane in exercise control group have extremely remarkably increases as compared with rest drug group (P<0.01) . The nember of Glut4 on adipocyte plasma membrane in exercise drug group have extremely remarkably increases as compared with rest drug group (P<0.01). The nember of Glut4 on adipocyte plasma membrane in exercise control group significantly increases as compared with exercise drug group(P<0.05)The nember of Glut4 on adipocyte plasma membrane in rest drug group significantly increases as compared with rest control group(P<0.05)(3)The insulin sensitivity in both exercise control and exercise drug groups significantly increases (P<0.05). Galantide makes the insulin sensitivity significantly drop (P<0.05), The insulin sensitive index in the rest drug group extremely remarkably drops after the experiment (P<0.01). The insulin sensitive index in the exercise drug group extremely drops after the experiment (P<0.05).Conclusion: the endogenous galanin one hand inhibit insulin secretion another hand as an essential important attribute to maintenance the insulin sensitivity in both of rest and exercise conditions; Exercise may enhance the insulin sensitivity by ways including increasing the Glut4 quantity and promoting the Glut4 transportation onto the plasma cell membrane, but have on significantly to production of Glut4. However, galanin may be mainly through increasing the Glut4 transportation onto the cell membrane or improving the activity of Glut4 increases the insulin sensitivity .