Misson J P, Edwards M A, Yamamoto M, Caviness V S
Eunice Kennedy Shriver Center, Department of Developmental Anatomy and Pathology, Waltham, MA 02254.
Brain Res. 1988 Feb 1;466(2):183-90. doi: 10.1016/0165-3806(88)90043-0.
Radial glial cells of the embryonic murine cerebral wall are selectively labeled by staining with antibody RC1. In order to study the mitotic cycling of these cells, we combined RC1 immunohistochemistry and autoradiographic analysis following [3H]thymidine injection at 1, 2, 6, 48 h prior to sacrifice. Many radial glial cells, i.e. RC1-positive cells, incorporate the DNA tracer and hence must be mitotically active. Other proliferative cells of the ventricular zone do not stain with RC1. With the transition from S to M phase, the nuclei of the radial glial cells participate in the interkinetic 'to-and-fro' nuclear translocation characteristic of the non-radial glial cells of the ventricular zone. The density of radioactive grains over nuclei of both RC1-positive and negative cells of the ventricular zone becomes similarly reduced in the 48 h following the [3H]thymidine incorporation. Thus, the subpopulation of radial glia with nuclei within the ventricular zone which have incorporated the DNA tracer does not appear to become arrested in a prolonged G1 phase. The results suggest that the ventricular zone includes at least two subpopulations of stem cells, neuronal and radial glial. Radial glial cells, i.e. RC1-positive cells, are inferred to serve initially as a progenitor population for new radial glial cells. Later in development, they probably become a source of other cells of astroglial lineage.
胚胎期小鼠脑壁的放射状胶质细胞可通过用抗体RC1染色进行选择性标记。为了研究这些细胞的有丝分裂循环，我们在处死前1、2、6、48小时注射[3H]胸腺嘧啶核苷后，将RC1免疫组织化学和放射自显影分析相结合。许多放射状胶质细胞，即RC1阳性细胞，摄取了DNA示踪剂，因此必定具有有丝分裂活性。脑室区的其他增殖细胞不能被RC1染色。随着从S期到M期的转变，放射状胶质细胞的细胞核参与了脑室区非放射状胶质细胞特有的核往返运动。在掺入[3H]胸腺嘧啶核苷后的48小时内，脑室区RC1阳性和阴性细胞的细胞核上放射性颗粒的密度同样降低。因此，在脑室区内已摄取DNA示踪剂的放射状胶质细胞亚群似乎不会在延长的G1期停滞。结果表明，脑室区至少包括神经元和放射状胶质细胞这两个干细胞亚群。放射状胶质细胞，即RC1阳性细胞，最初被推断为新的放射状胶质细胞的祖细胞群。在发育后期，它们可能成为星形胶质细胞谱系其他细胞的来源。
