Differential effect of dopamine on mitosis in early postnatal albino and pigmented rat retinae
Differential effect of dopamine on mitosis in early postnatal albino and pigmented rat retinae
复制标题
DOI：
10.1002/neu.20200
复制
发表时间：
2006-01-01
期刊：
影响因子：
--
通讯作者：
Mobbs, P
中科院分区：
文献类型：
--
作者：
Kraij-Hans, I;Tibber, M;Mobbs, P
在白化病动物中，从视网膜色素上皮（RPE）释放的L-DOPA的水平不足被认为是导致下面的神经视网膜的异常发育的原因。左旋多巴通过直接作用于细胞或转化为多巴胺来降低细胞增殖水平，从而使视网膜神经发生正常化。在这里，我们报告多巴胺对出生后早期神经视网膜有丝分裂的影响，从白化病和有色大鼠，使用4D（x，y，z和时间）共聚焦显微镜。外源性多巴胺可显著抑制白化病动物视网膜的有丝分裂，但对有色动物无影响。由于在多巴胺存在下，进入心室区（VZ）并在其中分裂的细胞较少，因此我们得出结论，整个细胞周期受到影响。D1受体阻滞剂SCH 23390可抑制这些效应。因此，多巴胺在体外对有色和白化病大鼠神经视网膜的不同作用必须由D1受体的激活引起，D1受体从出生起就存在于视网膜中。D1受体的免疫组织化学标记表明，其分布模式是类似的色素沉着表型之间，但表达水平可能会升高白化病。标记在内网状层最强烈，但存在于整个成神经细胞层。这些研究结果进行了讨论，根据以前的报告，降低儿茶酚胺水平的白化病视网膜。(C)2005 Wiley Periodicals，Inc.
Insufficient levels Of L-DOPA, released from the retinal pigment epithelium (RPE), in albino animals are considered responsible for the abnormal development of the underlying neural retina. L-DOPA normalizes retinal neurogenesis by reducing levels of cell proliferation either by acting on the cells directly or by being converted into dopamine. Here we report the effects of dopamine on mitosis in early postnatal neural retinae from albino and pigmented rats, using 4D (x, y, z and time) confocal microscopy. Exogenous dopamine significantly prolongs mitosis in retinae from albino, but not pigmented, animals. As fewer cells move into and divide in the ventricular zone (VZ) in the presence of dopamine, we conclude that the overall cell cycle is affected. The D1 receptor blocker, SCH 23390, inhibits these effects. Thus, the differential effects of dopamine on neural retinae from pigmented and albino rats in vitro must result from the activation of D1 receptors, which are present in the retina from birth. Immunohistochemical labeling of D1 receptors shows that the pattern of their distribution is similar between pigmentation phenotypes, but levels of expression may be elevated in albinos. Labeling is most intense in the inner plexiform layer but is present throughout the neuroblastic layer. These findings are discussed in light of previous reports of reduced catecholamine levels in the albino retina. (C) 2005 Wiley Periodicals, Inc.