Westrum L E, Kott J N, Vickland H, Dong X M
Department of Neurological Surgery, University of Washington, Seattle 98195.
Exp Neurol. 1992 Jan;115(1):127-31. doi: 10.1016/0014-4886(92)90235-i.
We are using the rat olfactory system to study developmental aspects of neurotransplantation (TX). Age-related TX maturation and subsequent establishment of connections are of special concern. Previous studies of deafferentation by olfactory bulb (OB) removal suggested "critical" periods of plasticity in the system. We present here preliminary attempts at relating age of host receiving TX to maturation of the TX and its connections. This investigation used hosts of postnatal age (PN) 13-14 days with fetal donors at Embryonic Day 15; the former having one OB ablated and receiving a fetal donor OB TX immediately placed in the vacated space. The fetal tissue was labeled previously in utero with tritiated thymidine. After 2 months a small coagulation lesion was placed in the OB TX and 2 days later the tissue was taken, serially sectioned, and processed for [3H] autoradiography, degeneration, and olfactory marker protein (OMP). Extensively 3H-labeled OB TXs with localized small lesions were studied. The cellular architecture of the TX is less well organized than in normals but substantial OMP reactivity occurs throughout. Degeneration occurs mainly near the lesion and little if any degeneration is seen beyond the 3H-labeled TX tissue. The results show that OB TX survive and develop in the PN 13-14 age group as they do in the younger animals and that primary olfactory neurons likewise reinnervate the TX but that PN 13-14 TX efferent projections are far more limited than those of younger hosts.
我们正在利用大鼠嗅觉系统来研究神经移植（TX）的发育方面。与年龄相关的TX成熟以及随后连接的建立是特别关注的问题。先前关于切除嗅球（OB）导致去传入神经支配的研究表明该系统存在可塑性的“关键”时期。我们在此展示了将接受TX的宿主年龄与TX及其连接的成熟相关联的初步尝试。本研究使用出生后13 - 14天的宿主，胚胎供体为胚胎第15天；前者一侧OB被切除，并立即将接受的胚胎供体OB移植到腾出的空间中。胚胎组织先前在子宫内用氚标记的胸腺嘧啶核苷进行了标记。2个月后，在移植的OB中放置一个小的凝固性损伤，2天后取出组织，连续切片，并进行[3H]放射自显影、变性和嗅觉标记蛋白（OMP）处理。对具有局部小损伤的广泛3H标记的OB移植进行了研究。移植体的细胞结构不如正常组织组织良好，但整个区域都有大量的OMP反应性。变性主要发生在损伤附近，在3H标记移植组织之外几乎看不到变性。结果表明，OB移植在出生后13 - 14天的年龄组中能够存活并发育，就像在较年轻的动物中一样，并且初级嗅觉神经元同样会重新支配移植体，但出生后13 - 14天的移植传出投射比年轻宿主的要有限得多。
