Junquéro D, Modat G, Coquelet C, Bonne C
Laboratory of Cellular Physiology, University of Montpellier 1, France.
Exp Eye Res. 1990 Jul;51(1):49-53. doi: 10.1016/0014-4835(90)90169-u.
Corneal endothelium appears to be an important target tissue for retinoids and epidermal growth factor (EGF). We report here that retinoic acid, or its synthetic analogue CBS-211 A (10(-8)-10(-7) M) dose-dependently enhances the mitogenic effect of EGF on cultured bovine corneal endothelial cells (BCEC). Furthermore, retinoid treatment, especially with CBS-211 A, increases the EGF-binding capacity of BCEC without any modification of EGF receptor affinity. The addition of cycloheximide (0.5 microgram ml-1) to cultures simultaneously with retinoids suppressed the retinoid effect on EGF-binding, whereas this protein synthesis inhibitor was ineffective when added 24 hr later. These results suggest that retinoids could induce the expression of EGF receptors on BCEC as an early event. This study, which demonstrates a cooperation between retinoids and EGF in corneal endothelium, could explain the beneficial effect of retinoic acid previously reported on this tissue repair in vivo. Our data could offer clues for new pharmaceutical strategies in ophthalmology therapy.
角膜内皮似乎是类视黄醇和表皮生长因子（EGF）的重要靶组织。我们在此报告，视黄酸或其合成类似物CBS - 211 A（10⁻⁸ - 10⁻⁷M）可剂量依赖性地增强EGF对培养的牛角膜内皮细胞（BCEC）的促有丝分裂作用。此外，类视黄醇处理，尤其是用CBS - 211 A处理，可增加BCEC的EGF结合能力，而不改变EGF受体亲和力。与类视黄醇同时向培养物中添加环己酰亚胺（0.5微克/毫升）可抑制类视黄醇对EGF结合的作用，而当在24小时后添加这种蛋白质合成抑制剂时则无效。这些结果表明，类视黄醇可能作为早期事件诱导BCEC上EGF受体的表达。这项证明类视黄醇与EGF在角膜内皮中协同作用的研究，可以解释先前报道的视黄酸对该组织体内修复的有益作用。我们的数据可为眼科治疗的新药物策略提供线索。
