Luo M, Puymirat J, Dussault J H
Unité de Recherche en Ontogénèse et Génétique Moléculaire, Le Centre Hospitalier de l'Université Laval, Ste-Foy, Qué., Canada.
Brain Res Dev Brain Res. 1989 Mar 1;46(1):131-6. doi: 10.1016/0165-3806(89)90150-8.
By means of a monoclonal antibody (mab) against the rat liver nuclear L-T3 receptor (NT3R) and a polyclonal anti-GFAp serum, it has been possible to demonstrate nuclear thyroid hormone receptors in astrocyte cultures. On day 3, 47% of GFAp+ cell nuclei were labeled by 2B3 mab. Between day 3 and day 15, the number of GFA+ cell nuclei stained by 2B3 mab increased from 47 to 75%. Thyroid hormone nuclear receptors were present in fibrous and protoplasmic astrocytes. However, they developed asynchronously in both types of astrocytes. Indeed, 60% of fibrous astrocytes were stained by 2B3 mab on day 3 and this percentage reached 77% after 8 days in vitro. In contrast, only 30% of protoplasmic astrocytes were immunoreactive for 2B3 mab on day 3 and this percentage increased slowly reaching 47% on day 8 and around 75-80% on day 15. By immunoblotting, the monoclonal antibody recognized two bands of proteins with a molecular weight of 57 and 45 kDa respectively. These proteins have the same electrophoretic mobility as [125I]bromoacetyl-LT3 rat liver nuclear L-T3 receptor. This paper presents the first immunocytochemical localization of nuclear L-T3 receptors in astrocyte cultures. Furthermore, we show that thyroid hormone receptors develop more rapidly in fibrous than in protoplasmic astrocytes.
借助一种针对大鼠肝细胞核L-T3受体（NT3R）的单克隆抗体（mab）和一种抗GFAP多克隆血清，已能够在星形胶质细胞培养物中证实甲状腺激素核受体的存在。在第3天，47%的GFAP+细胞核被2B3 mab标记。在第3天至第15天之间，被2B3 mab染色的GFAP+细胞核数量从47%增加到75%。甲状腺激素核受体存在于纤维型和原浆型星形胶质细胞中。然而，它们在两种类型的星形胶质细胞中发育不同步。实际上，在第3天，60%的纤维型星形胶质细胞被2B3 mab染色，在体外培养8天后这一比例达到77%。相比之下，在第3天，只有30%的原浆型星形胶质细胞对2B3 mab有免疫反应，这一比例缓慢增加，在第8天达到47%，在第15天达到约75 - 80%。通过免疫印迹法，该单克隆抗体识别出两条分别具有57 kDa和45 kDa分子量的蛋白条带。这些蛋白与[125I]溴乙酰-LT3大鼠肝细胞核L-T3受体具有相同的电泳迁移率。本文首次报道了星形胶质细胞培养物中核L-T3受体的免疫细胞化学定位。此外，我们表明甲状腺激素受体在纤维型星形胶质细胞中的发育比在原浆型星形胶质细胞中更快。
