大鼠肠粘膜组织鲜味受体传感动力学研究  

Sensing Kinetics of Umami Receptor in Rats Intestinal Mucosa

作　　者：刘谡瑶 庞广昌[2] 刘源 LIU Su-yao;PANG Guang-chang;LIU Yuan(College of Food Science and Technology,Shanghai Ocean University,Shanghai 201406,China;College of Biotechnology and Food Science,Tianjin University of Commerce,Tianjin 300134,China;Shanghai Jiao Tong University School of Agriculture and Biology ,Shanghai200240,China)

机构地区：[1]上海海洋大学食品学院,上海201406 [2]天津商业大学食品科学与生物技术学院,天津300134 [3]上海交通大学农业与生物学院,上海200240

出　　处：《食品工业科技》2018年第23期84-88,110,共6页Science and Technology of Food Industry

基　　金：国家自然科学基金(31622042;31371790;31271900);国家"十三五"重点研发计划项目任务(2016YFD0400803;2016YFD0401501)

摘　　要：鲜味受体不仅存在于味蕾组织,也存在于肠黏膜等组织中。本研究以SD大鼠为研究材料,通过固定化肠黏膜组织制成传感器,对代表性鲜味物质:谷氨酸钠、肌苷酸二钠、鸟苷酸二钠进行了受体传感动力学测定。结果表明,鲜味受体与配体呈现出与酶-底物相似的双曲线动力学特征。通过双倒数作图法,求出分别与其受体作用的激活常数K为:K_a=1.136×10^(-13)mol/L,K_b=1.443×10^(-13)mol/L,K_c=2.080×10^(-13)mol/L。说明肠粘膜组织对这三种鲜味物质的传感敏感性排序为:谷氨酸钠、肌苷酸二钠、鸟苷酸二纳。根据这3种鲜味成分的动力学特性,计算出谷氨酸钠、肌苷酸二钠、鸟苷酸二钠平均每个细胞上的受体个数分别为:2.30、2.89、4.16/cell;由此看出K越低,说明激活细胞内的活性越高,则信号越敏感,则达到受体-配体饱和时平均每个细胞上受体数目越少。谷氨酸钠、肌苷酸二难、鸟苷酸二钠信号放大倍数分别为:N_1=1.9055×10~4,N_2=1.6642×10~4,N_3=6.0799×10~3。此结果和所得到的活性常数与平均每个细胞上的受体数量相对应,说明配体与受体作用产生的信号输出的效率越高,则信号放大倍数也越大。综上,该传感器可定量化描述肠粘膜组织中的受体对相应配体的传感作用(激活常数)、效应受体个数和细胞信号级联放大作用,动力学参数可以为评价肠黏膜系统的各种受体对相应配体的传感活性及生理作用提供评价方法和科学依据。Umami receptors existed not only in taste tissues,but also in intestinal mucosa and other tissues.In this study,SD rats as research meterials,the sensor was prepared by immobilizing intestinal mucosal tissue to sence the representative umami substances:Sodium glutamate,disodium inosinate,disodium guanylate.The results showed that,the umami recepter and the ligand exhibited a hyperbolic kinetic features similar to enzyme-substrates.The Line weaver-Burk plot method was used to calculate umami substances and receptors activation constants,which were Ka=1.136×10-13mol/,Kb=1.443×10-13mol/L,Kc=2.080×10-13mol/L,respectively.The sensitivity of intestinal mucosal tissue to these three kinds of umami was summarized as follows:Sodium glutamate,disodium inosinate,disodium guanylate.The average number of intestinal mucosa receptors was calculated as:2.30,2.89,4.16/cell.It indicated that the lower of K,the more active the activation cell was,the more sensitive the signal was,the fewer receptors on average per cell when the receptor ligand was saturated.The cell signal amplification factors were N1=1.9055×104,N2=1.6642×104,N3=6.0799×103,respectively.The results and the resulting active constant and the average number of receptors on cells,and the signal output generated by ligand and receptor efficiency was higher,the signal magnification.In summary,in intestinal mucosa,the sensor could quantitatively describe the ligandreceptor action(receptors activation constants),receptor number and cell signal amplification factors,the kinetic parameters could provide an evaluation method and scientific basis for evaluating the sensing activity and the physiological function of various receptors in the intestinal mucosal system.

关 键 词：鲜味受体 肠黏膜 传感器 激活常数 受体个数 信号放大倍数 

分 类 号：TS201[轻工技术与工程—食品科学]