Cytological aspects of pineal development in rats and hamsters.
Cytological aspects of pineal development in rats and hamsters.
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大鼠和仓鼠松果体发育的细胞学方面。
DOI：
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发表时间：
1973
影响因子：
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通讯作者：
J. W. Clabough
中科院分区：
文献类型：
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作者：
J. W. Clabough
越来越多的证据支持这一假说，即通过系统进化，哺乳动物松果体细胞是从松果体光感受器细胞进化而来的，而松果体光感受器细胞是某些低等脊椎动物的特征。在本研究中，发育中的松果体在胎鼠和仓鼠进行了研究，在光镜和电镜水平，以确定是否或不松果体细胞的个体发育提供线索，其系统发育起源。大鼠胎仔的松果体发育发生在妊娠的最后8天（14-22），仓鼠胎仔的松果体发育发生在妊娠的最后5天（11-16）。松果体具有许多相似之处，在这两个物种，因为它从一个管状外翻的间脑屋顶发展成为一个紧凑的细胞团。不同的细胞类型不能很容易区分胎儿材料从任何物种。在这两种动物中，只要腔存在，与这些腔相邻的细胞就会表现出表面修饰，使人联想到正在发育的光感受器细胞，即，一种“椭圆体样”顶端细胞质隆起，通常含有一个或两个中心粒，并带有纤毛衍生物，表现出9 + 0管状构型。当松果体组织增生时，管腔和纤毛样结构消失。这些发现，当考虑与系统发育的研究，加强了假设，哺乳动物松果体包含细胞来自光感受器细胞系。
Evidence has been accumulating which supports the hypothesis that through phylogenetic evolution, the mammalian pinealocyte has evolved from the pineal photoreceptor-cell which is characteristic of certain lower vertebrates. In the present study, developing pineal glands in fetal rats and hamsters were studied at light and electron microscopic levels to determine whether or not the ontogenetic development of pineal cells affords clues to their phylogenetic origin. Pineal development in fetal rats occurs during the last eight days of gestation (14–22) and in fetal hamsters, during the last five days of gestation (11–16). The pineal gland exhibits many similarities in the two species as it develops from a tubular evagination of the diencephalic roof into a compact cellular mass. Different cellular types could not be readily distinguished in fetal material from either species. In both animals, as long as lumina persist, cells bordering on these lumina exhibit surface modifications reminiscent of developing photoreceptor-cells, i.e., an “ellipsoid-like” apical cytoplasmic bulge which often contains one or two centrioles and bears a ciliary derivative exhibiting a 9 + 0 tubular configuration. As pineal tissue proliferates, the lumina and cilium-like structures disappear. The findings, when considered with phylogenetic studies, strengthen the hypothesis that the mammalian pineal gland contains cells derived from the photoreceptor-cell line.