Majda B T, Harvey A R
Department of Anatomy and Human Biology, University of Western Australia, Nedlands, Perth.
J Neural Transplant. 1989;1(3-4):95-103. doi: 10.1155/NP.1989.95.
Tectal tissue was removed from rats at embryonic ages (E) E15, E18, E20 and postnatal day 0 (P0) and grafted onto the midbrain of newborn host rats. Six to 24 weeks after transplantation we examined 1) the growth characteristics of the grafts, 2) their morphology and 3) the pattern of retinal innervation of the grafted tissue. Graft survival was markedly affected by donor age. Transplants from E15 and E18 donors showed a survival rate of 90% which decreased to 35% when tissue was taken from E20 animals. Only one graft could be definitively identified in the P0 group. The ultimate volume of the graft was inversely related to donor age; grafts taken from E15 donors grew in size and produced the largest grafts, whereas E20 grafts showed a reduction in tissue volume from the time of implantation. Host retinal input was found in surviving grafts from all fetal donor ages (E15-E20). This input was always restricted to localized areas in the grafts containing high AChE activity; these areas are believed to contain presumptive superior collicular cells from the superficial layers. Thus, in tissue taken from fetal rats, it appears that altering the donor age does not affect the selectivity with which host retinal axons grow into and innervate specific areas within tectal grafts.
在胚胎期（E）E15、E18、E20以及出生后第0天（P0）从大鼠身上取出顶盖组织，并将其移植到新生宿主大鼠的中脑。移植后6至24周，我们检查了：1）移植物的生长特性；2）它们的形态；3）移植组织的视网膜神经支配模式。移植物的存活受到供体年龄的显著影响。来自E15和E18供体的移植物存活率为90%，而从E20动物获取组织时，存活率降至35%。在P0组中仅能明确鉴定出一个移植物。移植物的最终体积与供体年龄呈负相关；从E15供体获取的移植物体积增大，形成最大的移植物，而E20移植物从植入时起组织体积就减小。在所有胎儿供体年龄（E15 - E20）的存活移植物中均发现了宿主视网膜输入。这种输入总是局限于移植物中含有高乙酰胆碱酯酶（AChE）活性的局部区域；这些区域被认为含有来自表层的假定上丘细胞。因此，在取自胎鼠的组织中，改变供体年龄似乎并不影响宿主视网膜轴突生长并支配顶盖移植物内特定区域的选择性。
