PDF(Pubmed)
Abstract：
Motilin is a gastrointestinal hormone that is mainly produced in the duodenum of mammals, and it is responsible for regulating appetite. However, the role and expression of motilin are poorly understood during starvation and the weaning stage, which is of great importance in the seeding cultivation of fish. In this study, the sequences of Yangtze sturgeon (Acipenser dabryanus Motilin (AdMotilin)) motilin receptor (AdMotilinR) were cloned and characterized. The results of tissue expression showed that by contrast with mammals, AdMotilin mRNA was richly expressed in the brain, whereas AdMotilinR was highly expressed in the stomach, duodenum, and brain. Weaning from a natural diet of T. Limnodrilus to commercial feed significantly promoted the expression of AdMotilin in the brain during the period from day 1 to day 10, and after re-feeding with T. Limnodrilus the change in expression of AdMotilin was partially reversed. Similarly, it was revealed that fasting increased the expression of AdMotilin in the brain (3 h, 6 h) and duodenum (3 h), and the expression of AdMotilinR in the brain (1 h) in a time-dependent manner. Furthermore, it was observed that peripheral injection of motilin-NH2 increased food intake and the filling index of the digestive tract in the Yangtze sturgeon, which was accompanied by the changes of AdMotilinR and appetite factors expression in the brain (POMC, CART, AGRP, NPY and CCK) and stomach (CCK). These results indicate that motilin acts as an indicator of nutritional status, and also serves as a novel orexigenic factor that stimulates food intake in Acipenser dabryanus. This study lays a strong foundation for the application of motilin as a biomarker in the estimation of hunger in juvenile Acipenser dabryanu during the weaning phase, and enhances the understanding of the role of motilin as a novel regulator of feeding in fish.
摘要：
胃动素是一种胃肠激素，主要在哺乳动物的十二指肠产生，它负责调节食欲。然而,在饥饿和断奶阶段，对胃动素的作用和表达知之甚少，这对鱼类的播种种植非常重要。在这项研究中,克隆并鉴定了长江st鱼（AcipenserdabryanusMotilin（AdMotilin））胃动素受体（AdMotilinR）的序列。组织表达结果表明,与哺乳动物相比,AdMotilinmRNA在脑中丰富表达,而AdMotilinR在胃中高表达，十二指肠,和大脑。从T.Limnodrilus的天然饮食断奶到商业饲料，在第1天至第10天的时间内显着促进了AdMotilin在大脑中的表达，并且在用T.Limnodrilus重新喂养后，AdMotilin的表达变化被部分逆转。同样，发现禁食增加了AdMotilin在大脑中的表达（3小时，6h）和十二指肠（3h），和AdMotilinR在大脑中的表达（1h）呈时间依赖性。此外，观察到外周注射胃动素-NH2增加了长江st的食物摄入量和消化道的填充指数，伴随着AdMotilinR和食欲因子在大脑中表达的变化（POMC，CART,AGRP,NPY和CCK）和胃（CCK）。这些结果表明，胃动素作为营养状况的指标，并且还可以作为一种新型的促食欲因子，刺激达布里亚斯的食物摄入。本研究为将胃动素作为生物标志物应用于断奶期幼鱼摄氏期饥饿程度的评估奠定了坚实的基础。并增强了对胃动素作为一种新型鱼类喂养调节剂的作用的理解。
