奶牛乳腺长链脂肪酸转运的研究进展

奶牛乳脂中的长链脂肪酸（LCFA）JL乎全部来源于从消化道吸收并转运人血液的食物外源性LCFA，然后跨膜进入乳腺上皮细胞参与乳脂合成，而参与LCFA跨膜运输的脂肪酸转运蛋白有：脂肪酸转运蛋白家族（Fattyacid transport proteins，FAPTs）、脂肪酸转位酶（Fatty acid translocase，FAT／CD36）、脂肪酸结合蛋白家族（Fattyacid binding proteins，FABPs）和小窝蛋白（Caveolinproteins）。文章在综述LCFA跨膜运输研究的基础上，重点介绍4种LCFA转运蛋白的研究进展，发现在奶牛乳腺中表达的只有FAT／CD36和FABPs，而FATPs和小窝蛋白在奶牛乳腺中是否表达并参与LCFA的转运仍有待进一步研究确定。因此，应利用营养学、分子生物学和细胞生物学等方法，在体内和体外对FAT／CD36、FABPs、FATPs和小窝蛋白在泌乳期奶牛乳腺中的表达规律、作用机理进行深入研究，以探明其在乳腺LCFA转运中的作用及调控机制．并为优化乳脂组成实施的营养调控提供科学依据。

Advances in long-chain fatty acid transport in cow mammary gland

Almost all long-chain fatty acids of bovine milk fat originate from dietary lipids which are digested and absorbed in the gastrointestinal tract and then transported in the blood. Long-chain fatty acids go through the blood vessel wall and the plasma membrane to move into the epithelial cells to participate in the synthesis of milk fat in the mammary gland. Four proteins which have been found to be possibly associated with the transmembrane transport of long chain fatty acids are as follows： fatty acid transport proteins （FAPTs）, fatty acid translocase （FAT/CD36）, fatty acid binding proteins （FABPs） and caveolin proteins. Based on the previous research of transmembrane, the recent research progress on the four kinds of fatty acid transport protein and the fatty acid transport in the mammary gland of cows were reviewed. It was found that only FAT/ CD36 and FABPs were expressed in cow mammary gland. It was not definite whether FATPs or caveolin had anything to do with LCFA transport. Besides, in vitro and in vivo expression role and function mechanism of the above four proteins in cow mammary gland in lactation period were intensively studied so as to clarify their role in mammary gland LCFA transport and provide scientific references for nutrition regulation of cream composition optimization.