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视黄酸（Ｒｅｔｉｎｏｉｃａｃｉｄ，ＲＡ）是细胞的分化诱导剂。近年来发现ＲＡ能广泛作用于细胞，引起一系列生理功能改变，并能使多种肿瘤细胞向正常细胞分化。ＲＡ对细胞基本生物学行为—细胞粘附的影响了解甚少。我们发现３２μｍｏｌ／ＬＲＡ能使ＮＩＨ３Ｔ３细胞与纤连蛋白（Ｆｉｂｒｏｎｅｃｔｉｎ，Ｆｎ）的粘附能力增加２０％，但并不促进细胞与多聚赖氨酸的粘附。采用抗整合蛋白α５亚基单抗和抗整合蛋白β１亚基单抗，并通过细胞流式仪测定细胞膜表面整合蛋白含量，发现ＲＡ作用细胞２４小时并不改变细胞表面α５β１亚基的蛋白含量。ＲＡ可使３Ｈ－甘露糖参入ＮＩＨ３Ｔ３细胞增加５８％。进一步发现ＲＡ使ＮＩＨ３Ｔ３细胞表面Ｎ－糖链三、四天线复杂型（可含β１，４Ｎ－乙酰氨基葡萄糖）增加１３％。上述结果提示ＲＡ促进细胞与Ｆｎ粘附可能是通过改变细胞膜糖蛋白糖链的含量和结构而实现的。
Retinoic acid (RA) is a cell differentiation inducer. In recent years, RA has been found to act broadly on cells, causing a series of changes in physiological functions and differentiating multiple tumor cells into normal cells. The effect of RA on basic biological behavior of cells, cell adhesion, is poorly understood. We found that 32μmol / LRA increased the adhesion of NIH3T3 cells to fibronectin (Fn) by 20%, but did not promote the adhesion of cells to polylysine. The anti-integrin α5 subunit monoclonal antibody and anti-integrin β1 subunit monoclonal antibody were used to determine the content of integrin on cell membrane surface by means of flow cytometer. It was found that the RA-treated cells did not change the protein content of α5β1 subunit on the cell surface for 24 hours. RA increased 3H-mannose incorporation into NIH3T3 cells by 58%. It was further found that RA increased the N, N-glycosylated three- and four-antenna complex on the surface of NIH3T3 cells (which could contain β1,4N-acetylglucosamine) by 13%. The above results suggest that RA promotes cell adhesion to Fn probably by altering the content and structure of glycoprotein sugar chains in the cell membrane.