猫视网膜多巴胺能无长突细胞发育的中央—周边梯度  

A DISTINCT CENTROPERIPHERAL GRADIENT OF DEVELOPMENT IN DOPAMINERGIC AMACRINE CELLS OF CAT RETINA

作　　者：王厚华[1] 吕建利[1] 朱慧[1] 

机构地区：[1]中国科学院上海生理研究所

出　　处：《实验生物学报》1991年第2期159-164,共6页Acta Biologiae Experimentalis Sinica

基　　金：国家自然科学基金

摘　　要：本文报道用酪氨酸羟化酶(TH)免疫细胞化学方法标记猫视网膜多巴胺(DA)能无长突细胞发育的中央—周边梯度。TH阳性反应的I型DA能无长突细胞在发育成熟过程中呈现时空顺序的中央—周边梯度:(1)P_1时期分化较高的细胞,即染色深,胞体大,具有2—4支树突,分枝分布于内网状层(IPL),最外缘的星状Ⅰ_1类细胞大都集中于视网膜的中央部位;而分化较低的细胞,即染色淡,胞体小,具有1—2支树突,分枝分布于IPL外层和中层的不规则形Ⅰ_3类细胞大都集中于视网膜的周边部位;介于两者之间的Ⅰ_2类细胞散在分布于整个视网膜。它们形成了空间分布上的中央—周边分化成熟梯度。(2)随着发育进程,Ⅰ_1类细胞数增多,分布区逐渐从中央向四周扩展,由占视网膜总面积的30%(P_1时)增至65%(P_6时),P_(13)时达97%。开眼后P_(13)时,由于Ⅰ_1类细胞分布已扩展至周边,中央区和周边区间细胞平均直径和树突发育成熟程度的差别逐渐缩小,Ⅰ型DA能无长突细胞发育成熟的中央—周边梯度明显减弱。至P_(23)时,周边区细胞对TH抗体免疫反应强度以及形态学上成熟程度均相似中央区者,上述中央—周边梯度特征则完全消失。I型DA能无长突细胞发育成熟过程中呈现时空顺序的中央—周边梯度特征是视网膜个体发育过程中的暂时现象,它与视网膜中一些神经发生过程存在平行关系。它在视网膜神经发生中的作用,文中进行了讨论。The centro-periphcral gradient of development in dopamincrgic (DA) amacrine cells of cat retina has been studied by TH immunocytochemical method.Type Ⅰ of TH immunoreactive neurons is typical DA cell. They reveal a clear centro-peripheral gradient of differentiation and maturation in space and time course during postnatal development. (1) At P_1 stage, the TH Ⅰ cells vary in TH immunoieactivity, soma sizes and dendritic maturation. Responding to degree of development, they can be divided into I_1, I_2 and I_3. The more differentiated I_1 cells, larger and darkly immuno-stained stellate cells mostly concen trats at central retina, while the less differentiated I_3 cells, smaller and lightly immunostained irregular cells concentrate at peripheral retina. I_2 cells of moderate differentiation distribute over all the retina. (2) During the postnatal development, from P_1 to P_(13), the dense area of the TH I_1 cells spreads peripherally in company with the increase of the total number of TH I_1 cells, comprising the cental 30% of the retina at P_1 , 65% at P_6 and almost the whole of the retina by P_(13).After eye opening, as the TH Ⅰ cells have spread at far peripheral region, the differences in soma diameters and dendritic maturation of TH Ⅰ cells between central and peripheral retina decrease gradually and the centro-periphcral gradient of maturity of TH Ⅰ cells becomes less distinct. At P_(23), no significant difference is visible in either soma diameter or dendritic maturation in these two areas; thus, the centro-peripheral gradient is no longer apparent.The centro-periphcral gradient of development in dopamincrgic amacrine cells is the transient occurence in the postnatal developmcnt of cat rctipa. It is closely coincident in space and time with several events of histogenesis. Its significance in the cytogenesis of the cat retina has been disscussed.

关 键 词：猫视网膜 无长突细胞 中央周边梯度 

分 类 号：Q436[生物学—生理学]