[Expression of orexin receptor 1 in rat pancreatic tissue with alimentary obesity].

Objective: To identify the presence of orexin receptor 1 (OXR1) in obese rat pancreas and clarify its effect and mechanism on body weight and metabolic index in obese rats.

Methods: The obese rat model was established a high-fat diet. And the serum levels of glucose, triglyceride and insulin were measured by Mini-Blood Glucose meter, biochemical enzymatic method and chemiluminescent immunoassay. The pancreatic expression of OX1R protein was identified by immunohistochemistry. After an intracerebroventricular infusion of orexin receptor 1 antisense oligodeoxynucleotide (OX1R-PS-ODNs), the effect on OX1R protein was detected in rat pancreatic tissue with obesity.

Results: After feeding for 8 weeks, high-fat diet rats appear alimentary obesity body weight, serum glucose, insulin, triglyceride and cholesterol of high-diet rats were higher than those in the control group (P < 0.05). The expression of OX1R protein was located in the cytoplasm of pancreas Islet β-cells. The expression of OX1R protein in obese rat pancreas decreased around 16% versus the normal group (P < 0.05). After the obese rats were treated by OX1R-PS-ODNs for 72 hours, the expression of OX1R protein in pancreas declined from 82 ± 6 to 65 ± 4, reduced about 21% compare with control group (P < 0.01).

Conclusion: The expression of OX1R protein is found in pancreas Islet β-cells. Hypothalamic orexin system can intervene the expression of OX1R protein in rat pancreatic tissue with alimentary obesity. And it may participate in the occurrence of obesity and the metabolic regulation of serum glucose and insulin.