The pearl mutation accelerates the schedule of natural cell death in the early postnatal retina.
The pearl mutation accelerates the schedule of natural cell death in the early postnatal retina.
复制标题
珍珠突变加速了出生后早期视网膜中自然细胞死亡的进程。
DOI：
10.1007/bf00231258
复制
发表时间：
1990
影响因子：
2
通讯作者：
Pinto,LH
中科院分区：
文献类型：
--
作者：
Williams,MA;Piñon,LG;Linden,R;Pinto,LH
出生后珍珠突变小鼠视网膜神经节细胞层中最大程度出现核固缩的时间早于正常小鼠（林登and平托1985）。神经节和移位的无长突细胞和神经胶质细胞都位于神经节细胞层。因此，为了表明神经节细胞本身受到影响，我们对出生后（PND）0、4、12和成年小鼠视神经中存活轴突的数量进行了计数。在PND 0时，珍珠突变小鼠具有139000 ± 2800（SEM）视神经轴突，比野生型小鼠多约8%（128000 ± 1，700;p= 0.031），但在PND 4时，珍珠突变小鼠的轴突比野生型小鼠少24%（分别为96000 ± 3700和119000 ± 4600;p= 0.008）。因此，在PND 0至4的时间间隔内，珍珠突变体失去的视网膜神经节细胞几乎是野生型小鼠的五倍。成年小鼠中存在的轴突数量几乎相等（野生型为56700 ± 3200，珍珠小鼠为52500 ± 2700 = 0.37）。我们通过计算视网膜各层中固缩核的数量来寻找视网膜其他神经元细胞死亡时间表变化的证据。在PND 4时，珍珠突变小鼠在成神经细胞层中具有比野生型小鼠更多的固缩核（分别为5000 ± 400和3900 ± 300;p< 0.05）。两种基因型的外核层出现固缩核的时间进程不同（ANOVA，F= 12.5，p < 0.001）。最显著的差异是在PND 20时，珍珠突变体（1300个）的固缩核数量多于野生型（480个;p= 0.002）。然而，两种基因型的成年人光感受器总数没有差异（野生型为3.6 × 106± 2.4 × 105，珍珠型为3.7 × 106± 3.3 × 105;p> 0.8）。这些结果综合起来表明，珍珠突变体的视网膜神经节细胞的自然细胞死亡发生在较早的时间，但存活至成年的视网膜神经元的总数不受突变的明显影响。
The time of maximal occurrence of pyknotic nuclei in the retinal ganglion cell layer of postnatal pearl mutant mice is earlier than that in normal mice (Linden and Pinto 1985). Both ganglion and displaced amacrine cells and glia populate the ganglion cell layer. Thus, in order to show that ganglion cells themselves are affected, we counted the numbers of surviving axons in the optic nerve of postnatal day (PND) 0, 4, 12 and adult mice. On PND 0, pearl mutant mice had 139000 ± 2800 (SEM) optic axons, about 8% more than wild-type mice (128000 ± 1,700;p= 0.031) but on PND 4, pearl mutants had 24% fewer axons than wild-type mice (96000 ± 3700 and 119000 ± 4600, respectively;p= 0.008). Thus, pearl mutants lose nearly five times as many retinal ganglion cells as wild-type mice in the interval from PND 0 to 4. The number of axons present in adult mice was nearly equal (56700 ± 3200 for wild-type and 52500 ± 2700 for pearl mutantsp= 0.37). We searched for evidence for changes in the schedule of cell death among other neurons of the retina by counting the number of pyknotic nuclei in the various retinal layers. On PND 4, pearl mutant mice had more pyknotic nuclei in the neuroblastic layer than wild-type mice (5000 ± 400 and 3900 ± 300, respectively;p< 0.05). The time-course of the appearance of pyknotic nuclei in the outer nuclear layer differed for the two genotypes (ANOVA, F=12.5,p< 0.001). The most striking difference was a greater number of pyknotic nuclei on PND 20 for the pearl mutants (1300) than for wild-type (480;p= 0.002). However, the total number of photoreceptors in adults did not differ between the two genotypes (3.6 × 106± 2.4 × 105for wildtype and 3.7 × 106± 3.3 × 105for pearl;p> 0.8). These results, taken together, show that natural cell death occurs at an earlier time for retinal ganglion cells of pearl mutants, but that the total number of retinal neurons surviving to adulthood is not affected appreciably by the mutation.