Fan Weihong, Saito Shoichiro, Matsumura Shuichi
Graduate School of Natural Science and Technology, Gifu University, Yanagido, Gifu, Japan.
Faculty of Applied Biological Sciences, Gifu University, Yanagido, Gifu, Japan.
Transl Anim Sci. 2020 Feb 12;4(2):txaa019. doi: 10.1093/tas/txaa019. eCollection 2020 Apr.
Animals have precise recognition systems for amino acids and peptides that regulate their feeding behavior as well as metabolic responses. Because of their particular gastrointestinal structure, ruminants are expected to have unique mechanisms of amino acid regulation in the digestive tract. To better understand these mechanisms in the ruminant digestive tract, the expression of and was studied along the gastrointestinal tract of Japanese Black cattle through quantitative RT-PCR and immunohistochemistry. mRNA was detected ubiquitously along the gastrointestinal tract, and the most predominant expression was observed in the reticulum. In addition, the presence of Tas1r3 receptor was confirmed in the rumen through immunohistochemistry. The expression level of mRNA was higher in the forestomach (rumen, reticulum, and omasum) and small intestine (duodenum) than that in the tongue, and predominant expression was observed in the rumen. By contrast, a negligible amount of mRNA was detected in the abomasum and large intestine. Further studies on the roles of and in the digestive tract, in particular, in the four components of the stomach, will help us to understand the mechanisms of amino acids regulation in ruminants and provide the basis for formulating cattle diets to improve the health and productivity of cattle.
动物具有精确的氨基酸和肽识别系统，这些系统可调节它们的摄食行为以及代谢反应。由于反刍动物特殊的胃肠道结构，预计它们在消化道中具有独特的氨基酸调节机制。为了更好地了解反刍动物消化道中的这些机制，通过定量逆转录聚合酶链反应（qRT-PCR）和免疫组织化学方法，研究了日本黑牛胃肠道中[具体基因名称未给出]和[具体基因名称未给出]的表达情况。[具体基因名称未给出]mRNA在胃肠道中普遍存在，在网胃中观察到最主要的表达。此外，通过免疫组织化学在瘤胃中证实了Tas1r3受体的存在。[具体基因名称未给出]mRNA在前胃（瘤胃、网胃和瓣胃）和小肠（十二指肠）中的表达水平高于在舌中的表达水平，并且在瘤胃中观察到主要表达。相比之下，在皱胃和大肠中检测到的[具体基因名称未给出]mRNA量可忽略不计。进一步研究[具体基因名称未给出]和[具体基因名称未给出]在消化道中的作用，特别是在胃的四个组成部分中的作用，将有助于我们了解反刍动物氨基酸调节机制，并为制定牛饲料配方以改善牛的健康和生产力提供依据。
