室旁核注射GLP-1及拮抗剂对大鼠胃组织nesfatin-1表达的影响

The Effect of GLP-1 and Its Antagonist Paraventricular Injection on Nesfatin-1 of Rats Stomach

目的:探讨下丘脑室旁核(pareventricular,PVN)注射胰高血糖素样肽-1(GLP-1)及其受体拮抗剂Exendin(9-39)后胃组织核组蛋白2(NUCB2)/nesfatin-1表达的影响。方法:选取48只雄性Wistar大鼠,随机分为6组,生理盐水组,四种不同剂量GLP-1组(0.003 nmol/10μL,0.03 nmol/10μL,0.3 nmol/10μL,3 nmol/10μL),30 nmol Exendin(9-39)+3 nmol GLP-1(E+G)组,每组8只。PVN区埋置套管并按每组要求分别经套管给予GLP-1及Exendin(9-39)等药物。给药2小时后处死大鼠并取胃组织,实时荧光定量RT-PCR法检测各组胃组织NUCB2 m RNA表达。另外生理盐水组,3 nmo L GLP-1组及E+G组每组分别随机取6只大鼠的部分胃组织,用免疫组织化学法测胃粘膜NUCB2/nesfatin-1蛋白的表达情况。结果:实时荧光定量RT-PCR法发现3 nmo L GLP-1组大鼠胃组织NUCB2 m RNA表达量高于生理盐水组,差异有统计学意义(P<0.05),而其余各组大鼠胃组织NUCB2 m RNA表达与生理盐水组比较无统计学差异(P>0.05)。免疫组化结果显示3 nmo L GLP-1组胃粘膜NUCB2/nesfatin-1蛋白表达与生理盐水组、E+G组比较有统计学差异(P<0.05),生理盐水组大鼠胃粘膜NUCB2/nesfatin-1蛋白表达与E+G组比较无明显差异(P>0.05)。结论:PVN注射GLP-1能够促进胃组织NUCB2/nesfatin-1的表达,这一作用可能是通过激活GLP-1受体来完成的。

Objective： To investigate the expression of the NUCB2/nesfatin-1 in stomach tissues after injection different doses of GLP-1 and its antagonist Exendin （9-39） in the hypothalamus paraventricular （PVN）. Methods： Forty-eight male Wistar rats were ran- domly divided into six groups, saline group, four different dose of GLP-1 group（0.003 nmol/10 μL, 0.03 nmol/10 μL, 0.3 nmol/10 μL, 3 nmol/10 μL ）and 30 nmol Exendin（9-39） combined with 3 nmol GLP-1 （E＋G） group. Each group of the animals was implanted with in- dwelling cannulas in the PVN. In the first 7 days after surgery, we inject saline or drugs to the PVN via indwelling cannulas according to the experimental requirements. After 2 hours of the infusion, stomach issues of all the six groups were collected to detect the expres- sion of NUCB2 mRNA by real-time RT-PCR. Additionally, Saline group, 3 nmol GLP-1 group and E＋G group randomly select 6 rats re- spectively. A part of stomach tissue of each rats were used immunohistochemical method to detect the expression of NUCB2/nesfatin-1 proteins in stomach mucosa. Results The expression ofNUCB2 mRNA in the 3 nmol GLP-1 group is higher than saline group in stom- ach tissues （P〈0.05）, but the other dose GLP-1 groups have no different on the expression ofNUCB2 mRNA in stomach tissues （P〉0.05）. The Immunohistochemistry results show the expression of NUCB2/nesfatin-1 protein in stomach mucosa of 3 nmol GLP-1 group is high- er than the saline group and E＋G treated group （P〈0.05）. However, the expression of NUCB2/nesfatin-1 protein between saline group and E＋G treated group have no significantly different （P〉0.05）. Conclusion： PVN injection of GLP-1 can increase the expression of NUCB2/nesfatin- 1 in stomach tissues that may be via the activation of its specific receptors.