食欲肽 B 刺激正常和糖尿病大鼠胰腺胰岛素和胰高血糖素释放的机制。

Mechanism of orexin B-stimulated insulin and glucagon release from the pancreas of normal and diabetic rats.

机构信息

Department of Anatomy, Faculty of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates.

出版信息

Pancreas. 2011 Jan;40(1):131-6. doi: 10.1097/MPA.0b013e3181f74b4b.

DOI:10.1097/MPA.0b013e3181f74b4b

PMID:20871474

Abstract

OBJECTIVES

To examine the pattern of distribution and effect of orexin B in the islets of normal and diabetic rats.

METHODS

Pancreatic tissue fragments collected from normal and diabetic (4 weeks after the onset of diabetes) rats were either processed for immunohistochemistry or treated with different concentrations (10 to 10 mol/L) of orexin B.

RESULTS

Orexin B-positive nerves were observed in the wall of blood vessels of both normal and diabetic rat pancreas. Orexin B is abundant in the islets of normal rats and colocalized with insulin in β cells. The number of orexin B-positive cells decreased after the onset of diabetes. Orexin B evoked significant (P<0.05) increases in insulin release from the pancreas of normal and diabetic rats. Propranolol, a β-adrenergic receptor antagonist, significantly (P<0.04) reduced the stimulatory effect of orexin B on insulin secretion. Orexin B also induced significant (P<0.05) increases in glucagon release from the pancreas of normal rats but failed to stimulate glucagon secretion from the pancreas of diabetic rats.

CONCLUSIONS

Orexin B stimulated insulin secretion in normal and diabetic rat pancreas through the β-adrenergic pathway. Orexin B may have an important role in the regulation of islet function.

摘要

目的

研究正常和糖尿病大鼠胰岛中食欲素 B 的分布模式及其作用。

方法

收集正常和糖尿病（糖尿病发病 4 周后）大鼠的胰腺组织片段，进行免疫组织化学染色或用不同浓度（10 至 10 mol/L）的食欲素 B 处理。

结果

在正常和糖尿病大鼠胰腺的血管壁中观察到食欲素 B 阳性神经。食欲素 B 在正常大鼠胰岛中含量丰富，并与β细胞中的胰岛素共定位。糖尿病发病后，食欲素 B 阳性细胞数量减少。食欲素 B 可显著（P<0.05）增加正常和糖尿病大鼠胰腺的胰岛素释放。β-肾上腺素能受体拮抗剂普萘洛尔显著（P<0.04）降低了食欲素 B 对胰岛素分泌的刺激作用。食欲素 B 还可诱导正常大鼠胰腺中胰高血糖素的显著（P<0.05）释放，但不能刺激糖尿病大鼠胰腺中胰高血糖素的分泌。