Calbindin-D28k在出生前人海马本部及下托神经元的表达及其变化

本实验采用免疫组织化学方法研究了１３～３８ 周人胎儿海马本部及下托含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ｋ 神经元的分布和发育。结果表明：在１３～１４ 周时，许多含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ｋ 锥体细胞可见于ＣＡ１ 区锥体细胞层中部及深部，随着胎龄增大，ＣＡ１ 区含Ｃａｌ－ｂｉｎｄｉｎ－Ｄ２８ｋ 锥体细胞的数量及密度逐渐下降，最终消失，并且这种下降及消失首先从含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ｋ 锥体细胞区浅部开始，然后向深部推进；在１３～２８ 周期间，ＣＡ２ 和ＣＡ３ 区也有许多含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ｋ 锥体细胞，但至３２ 周以及其后，ＣＡ３ 和ＣＡ２ 区则不见含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ｋ 锥体细胞，仅在ＣＡ２ 与ＣＡ１ 交界区见到少量弱染的含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ｋ 锥体细胞。此外，在２８～３８ 周期间，ＣＡ３ 和ＣＡ２ 区锥体细胞层周围可见许多含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ｋ 的苔藓纤维，其密度随胎龄增大而增加。１４～３８ 周期间，许多含Ｃａｌｂｉｎｄｉｎ－Ｄ２８ｋ 的锥体细胞也出现于下托锥体细胞层全层及前下托锥体细胞层浅部（细胞岛区）及中部。这些区域含Ｃａｌ－ｂｉｎｄｉｎ－Ｄ２８ｋ 锥体细胞的数量及染色强度在１４～２４ 周期间逐渐增

EXPRESSION AND CHANGES OF CALBINDIN-D28k IN NEURONS OF THE HIPPOCAMPUS PROPER AND SUBICULUM OF HUMAN PRENATAL BRAIN

Distribution and development of calbindin D28k(CB) containing neurons in the hippocampus proper and subiculum of human fetuses at 13～38 weeks were studied by means of immunohistochemistry. A large number of CB containing pyramidal cells were observed in the middle and deep part of the stratum pyramidale of CA1 at 13～14 weeks. The CB containing pyramidal cells were decreased in number and density and finally disappeared as age increased. This decline occurred at first in the superficial part of the region containing CB immunoreactive cells, and advanced toward the deep part, There were a lot of CB containing pyramidal cells in the pyramidal layer of CA2 and CA3 during 13～28 weeks, but none of these cells were observed in these regions from 32 weeks on. A small number of CB containing pyramidal cells in the border region between CA2 and CA1 were only weakly stained during 32～38 weeks. During 28～38 weeks, many mossy fibers were found near and within the stratum pyramidale of CA2 and CA3, and the density of these fibers was increased with age. A great number of CB containing pyramidal cells were observed in the whole layer of stratum pyramidale in the subiculum and in the superficial and middle part of the stratum pyramidale in presubiculum. The number and staining intensity of these cells in these regions were gradually increased during 14～24 weeks, and then gradually decrease during 24～38 weeks. CB containing nonpyramidal cells appeared in the stratum pyramidale of the hippocampus proper and subiculum at 32 weeks and were increased in number with age. They were mainly located in the superficial and middle part of the stratum pyramidale. However, CB containing nonpyramidal cells were always found in other layers beyond the stratum pyramidale in hippocampus proper during 13～38 weeks. In the subiculum and presubiculum, many CB containing nonpyramidal cells were seen in layer I during 13～28 weeks, but disappeared during 32～38 weeks. The present study for the first time demonstrated transient CB expression in pyamidal cells of the hippocampus proper and subiculum in human prenatal brain, and the extent and intensity of the CB expression varied with developmental stages and among regions in the hippocampal formation. (Figures 1～17 on plate 66,67)