【摘要】：黑素皮質(zhì)素4型受體(Melanocortin receptor-4,MC4R)作為調(diào)控動(dòng)物脂肪儲(chǔ)存和能量消耗的神經(jīng)元受體,其活動(dòng)與背肩胛棕色脂肪組織(Interscapular BAT,iBAT)產(chǎn)熱密切相關(guān)。其中以MC4R敲除鼠表現(xiàn)的過(guò)度肥胖為典型特征。在抗肥胖藥物臨床應(yīng)用中,胰淀素(Amylin)以其調(diào)節(jié)中樞神經(jīng)系統(tǒng)能量代謝平衡的作用被廣泛關(guān)注。近期研究中,MC4R被稱作治療肥胖癥的潛在作用靶點(diǎn),同時(shí)證明了 Amylin在機(jī)體能量代謝中起重要調(diào)控作用。本次研究以腹腔注射Amylin(50 μg/kg)及MC4R拮抗劑(SHU9119,50μg/kg)的C57BL/6小鼠為實(shí)驗(yàn)?zāi)Ｐ?通過(guò)對(duì)其采食量和背肩胛棕色脂肪處溫度的測(cè)定;對(duì)C-Fos和MC4R神經(jīng)元定位及共表達(dá)信息的免疫熒光技術(shù)檢測(cè);利用Western Blot技術(shù)檢測(cè)Amylin對(duì)下丘腦及iBAT組織中pACC、pAMPK、pERK、UCP1及MC4R等蛋白表達(dá)變化的影響。結(jié)果表明,Amylin可顯著降低禁食16h后小鼠的采食量(p0.01),且可顯著促進(jìn)iBAT溫度升高及C-Fos與MC4R在下丘腦神經(jīng)核團(tuán)中的表達(dá),同時(shí)提高共表達(dá)率;單獨(dú)注射SHU9119未見(jiàn)明顯變化,但聯(lián)合注射SHU9119和Amylin后,可阻斷由Amylin引起的抑制采食及iBAT溫度升高的效應(yīng),并抑制下丘腦區(qū)域C-Fos與MC4R神經(jīng)元共表達(dá)。另外,Amylin可顯著增加下丘腦和iBAT中pACC、pAMPK、UCP1及MC4R的蛋白表達(dá)量(p0.01)。注射Amylin可促進(jìn)下丘腦中pERK表達(dá),且抑制iBAT中pERK表達(dá)。聯(lián)合注射SHU9119和Amylin,可抑制由Amylin引起的pACC、pAMPK、pERK、UCP1及MC4R在下丘腦和iBAT中的表達(dá),其中單獨(dú)注射SHU9119未見(jiàn)明顯變化。綜上所述,通過(guò)腹腔注射Amylin,可促進(jìn)C-Fos和MC4R在下丘腦中神經(jīng)元中的表達(dá),并顯著抑制采食效應(yīng),促進(jìn)iBAT溫度升高。該調(diào)控過(guò)程與pACC、pAMPK、pERK信號(hào)通路及UCP1、MC4R密切相關(guān)。揭示了 Amylin和MC4R途徑在調(diào)節(jié)動(dòng)物攝食行為及產(chǎn)熱上的作用及其相互關(guān)系。結(jié)果提示,Amylin調(diào)節(jié)攝食行為和溫度升高的作用可部分受MC4R途徑介導(dǎo)。為理解MC4R介導(dǎo)Amylin調(diào)控中樞產(chǎn)熱通路及推動(dòng)Amylin在治療肥胖等疾病的應(yīng)用中提供理論依據(jù)。
[Abstract]:Melanocortin receptor-4 (MC4R) is a neuronal receptor regulating fat storage and energy expenditure in animals. The activity of MC4R is closely related to heat production in Interscapular fat tissue (Interscapular bat). The MC4R knockout mice were characterized by obesity. In the clinical application of anti-obesity drugs, amylin (Amylin) has been widely concerned because of its role in regulating energy metabolism balance in central nervous system. Recent studies have identified MC4R as a potential target for the treatment of obesity and has demonstrated that Amylin plays an important role in regulating energy metabolism in the body. In this study, we used C57BL/6 mice injected intraperitoneally with Amylin (50 渭 g/kg) and MC4R antagonist (SHU9119 ~ 50 渭 g/kg) as experimental models. The effects of Amylin on the expression of pACC-pAMPKUCP1 and MC4R in hypothalamus and iBAT were detected by Western Blot technique. The results showed that Amylin could significantly decrease the feed intake of mice after fasting for 16 h (p0.01), and could significantly increase the temperature of iBAT and the expression of C-Fos and MC4R in hypothalamic nucleus, and increase the coexpression rate of C-Fos and MC4R in hypothalamic nucleus. But after combined injection of SHU9119 and Amylin, the inhibitory effect of Amylin on feeding and the increase of iBAT temperature were blocked, and the co-expression of C-Fos and MC4R neurons in hypothalamus was inhibited. In addition, Amylin significantly increased the expression of pACC-pAMPK-UCP1 and MC4R in hypothalamus and iBAT (p0.01). Injection of Amylin could promote the expression of pERK in hypothalamus and inhibit the expression of pERK in iBAT. Combined injection of SHU9119 and Amylincould inhibit the expression of pACC-pAMPKPERKUCP1 and MC4R in hypothalamus and iBAT, but SHU9119 alone did not change significantly. In conclusion, intraperitoneal injection of Amylincould promote the expression of C-Fos and MC4R in hypothalamic neurons, significantly inhibit the feeding effect and promote the rise of iBAT temperature. This regulation process is closely related to the pACC-pAMPKPERK signaling pathway and UCP1 MC4R. The effects of Amylin and MC4R pathway on the regulation of feeding behavior and heat production in animals and their relationship were revealed. The results suggest that the effects of Amylin on feeding behavior and temperature rise may be partly mediated by MC4R pathway. In order to understand MC4R mediated Amylin regulation of central heat production pathway and promote the application of Amylin in the treatment of obesity and other diseases to provide theoretical basis.
【學(xué)位授予單位】：內(nèi)蒙古農(nóng)業(yè)大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2017
【分類號(hào)】：S852.2

【參考文獻(xiàn)】

相關(guān)期刊論文 前7條

1 鄭溜豐;彭健;;中樞神經(jīng)系統(tǒng)整合外周信號(hào)調(diào)節(jié)采食量的分子機(jī)制[J];動(dòng)物營(yíng)養(yǎng)學(xué)報(bào);2013年10期

2 左北瑤;錢宏光;;MC4R基因研究進(jìn)展[J];中國(guó)草食動(dòng)物;2011年05期

3 張紅勝;周s，

本文編號(hào)：2162825