Metformin may reduce food intake and body weight, but the anorexigenic effects of metformin are stil poorly understood. In this study, Sprague-Dawley rats were administered a single intracere-broventricular dose of metformin and compound C, in a broader attempt to investigate the regula-tory effects of metformin on food intake and to explore the possible mechanism. Results showed that central administration of metformin significantly reduced food intake and body weight gain, par-ticularly after 4 hours. A reduction of neuropeptide Y expression and induction of AMP-activated protein kinase phosphorylation in the hypothalamus were also observed 4 hours after metformin administration, which could be reversed by compound C, a commonly-used antagonist of AMP-activated protein kinase. Furthermore, metformin also improved lipid metabolism by reducing plasma low-density lipoprotein. Our findings suggest that under normal physiological conditions, central regulation of appetite by metformin is related to a decrease in neuropeptide Y gene expres-sion, and that the activation of AMP-activated protein kinase may simply be a response to the anorexigenic effect of metformin.

测定脑胶质瘤患者神经肽、神经降压素的含量变化及意义

Objective To investigate the change of neuropeptide Y(NPY)and neurotensin(NT)in pqtients with brain glioma.Method The concentration of NPY and NT in and around brain glioma tissue and plasma were detected with inequilibrant radio－ imunology method.Result NPY concentrqtion in brain glioma tissue was obviously higher than that in tissue around the tumor(P<0.01).The Concentration of NT in brain glioma tissue was obviously higher that in tissue around the glioma(P<0.01).Conclusion Detection of NPY and NTin brain glion aprovides basis for further study on brain glioma and explainning dlinical and imaginal symiptom of brain glioma.

神经肽Y在中枢神经系统中调控能量摄入和血糖稳态的作用机制

神经肽Y(neuropetite Y,NPY)是由特定的36个氨基酸组成,是人和哺乳动物神经系统内含量为丰富的活性多肽之一[1].参与机体的某些生理功能的调控,从而对机体的摄食行为、情绪、大脑皮层兴奋性、下丘脑与垂体间的信号联系、心血管生理功能及交感神经功能等进行有效调节和高效调控.神经肽Y由于能调控能量摄入及为治疗肥胖提供了新的治疗方法,近几年来备受青睐,其研究前景非常乐观.与瘦素(leptin)及胃肠激素FGF19[2](或者称之为FGF15,在啮齿类动物体内)共同改善代谢、调节能量摄入、改善糖耐量功能.

AIM: To study the mechanism of myocardial injury after brain ischemia-reperfusion in aged rats from the changes in Dopamine (DA), Noradrenalin (NE), Epinephrine(E) and Neuropeptide Y(NPY).METHODS: Young (5 months) and aged (20 months or more) rats were divided into model groups and normal control groups, respectively. We observed the following items in rats with 60 minute reperfusion after 30 minute brain ischemia: the pathological changed of myocardium, the activities of lactic dehydrrogenase(LDH), creatine phosphokinase(CPK), the contents of NE, DA, E, NPY. RESULTS:The CPK and LDH activities in the young model rats were higher than those in the young control rats was higher than that in the young control rats (P＜0.05). The serum CPK activity in the aged control rats was higher than that in the young control rats (P＜0.05). The myocardial CPK activity was higher in the aged model rats compared with the young molel rats (P＜0.05) and was higher in aged control rats compared with the young control rats (P＜0.01). The myocardial LDH activity was lower in the aged control rats than that in the young control rats (P＜0.05) and aged model rats (P＜0.01). The serum NE level, the level of NE and DA in the hypothalamus were higher obviously than those in the young control rats. The serum NE contents in the two model groups (young and aged) were higher respectively than the two control rats (young and aged). The following items’ contents were higher in the aged model rats than in the young model rats: serum NE, serum E, hypothalamus NE. The hypothalamus NE and E content was lower in the aged model rats than in te aged control rats. NPY level in the brain tissue was lower in the aged control rats than that in the young control rats and aged model rats (P＜0.05).CONCLUSION: The myocardial injury after brain ischemia-reperfusion was concerned with the enhanced excitability of sympathetic-adrenal system, espectially in the aged rats. However, the change in myocardial enzyme was not serious in the aged rats compared with young rats.