高血压已是当前世界上死亡率最高的疾病之一，我国已超过2亿人正面临高血压及其并发症的威胁。泥鳅作为中国传统药食同源体，对高血压、贫血等心血管疾病都有辅助治疗作用。在泥鳅蛋白的定向酶解及抗ACE活性肽分离的基础上，本项目拟以抗ACE活性最高的四肽AHLL为研究对象，通过体外Caco-2模型，从细胞和分子水平上研究泥鳅蛋白源抗ACE活性肽AHLL的吸收机制：明确Caco-2细胞摄取AHLL的量效关系、时效关系、热效关系及pH的影响，筛选出细胞吸收的依赖因子；以P-糖蛋白、代谢酶（CYP3A4）及表观二级动力学模型多角度分析Caco-2细胞对AHLL的外排特性，弄清细胞摄取与外排的关联性；探明Caco-2细胞AHLL的跨膜转运方式，最终揭示AHLL的吸收机制。本项目首次将Caco-2细胞模型应用在泥鳅蛋白源抗ACE活性肽的吸收理论研究，为泥鳅功能性食品的开发提供理论依据，具有重要的科学意义。

Currently, hypertension is one of the world's deadliest diseases. More than 200 million Chinese people are facing the threat of hypertension and its complications. As a traditional food in China, loach with medical efficacy plays a positive role in adjuvant therapy of hypertension, anemia and cardiovascular diseases. On the basis of loach protein controllable enzymolysis and purification of angiotensin-Ⅰ-converting enzyme inhibitory peptides,the absorption mechanism of tetrapeptide AHLL with the strongest activity will be studied through Caco-2 cell model in vitro in this project. The effects of time, concentration, temperature and pH on the uptake of AHLL are demonstrated，and the dependent factors are screened. It analyzes the efflux of AHLL widely and deeply with P-glycoprotein, metabolic enzyme CYP3A4 and apparent two-order kinetics model. The relationship between absorption and effllux is synthesized. It studies the transepithelial transport of AHLL definitely. At last, the absorption mechanism of AHLL is clarified. This is the first time to apply Caco-2 cell model to the absorption mechanism of loach angiotensin-Ⅰ-converting enzyme inhibitory peptide. It will provide a theoretical basis for the development of functional loach foods with vital scientific significance.