Wakai S, Meiselman S E, Brightman M W
Brain Res. 1986 Oct 29;386(1-2):209-22. doi: 10.1016/0006-8993(86)90157-5.
The efficacy with which circulating horseradish peroxidase (HRP) spreads from transplants into the brain's interstitial spaces (IS), was assessed by 3 factors: graft type, site and age. Pieces of skeletal muscle, skin or entire superior cervical ganglion (SCG) were inserted into the IV ventricle (ventricular) or substance of the brain (parenchymal). The age of the grafts, i.e. the intervals after transplantation, were 1, 3, 6 and 12 months. Generally, HRP spread into the IS to about the same extent from ventricular muscle and skin autografts--1 mm, but less from parenchymal SCG allografts--0.5 mm. The spread from all grafts--ventricular and parenchymal--diminished with time. Exudation distance from muscle was the same as that from skin grafts for the first 6 months, but by 1 year, the penetration was significantly greater from muscle than from skin transplants. The flow of HRP was more extensive from parenchymal SCG grafts than from parenchymal muscle and skin grafts at 6 and 12 months. In some of the 6 and 12 month old parenchymal grafts of muscle and skin, no detectable HRP was extravasated. HRP consistently penetrated the brain more deeply from ventricular skin and muscle grafts than from parenchymal ones because more tissue mass survived in ventricular than in parenchymal autografts. Though care was taken not to damage the brain surface during ventricular insertion, there was a consistent, vigorous, collateral sprouting of, as yet unidentified, cranial nerves. These sprouts innervated muscle and skin autografts which, consequently, were able to survive for at least 1 year and contained vessels permeable to HRP. Allografts of muscle between inbred strains did not become innervated, survived for only 2 months and contained the central, barrier type of vessels, but not their intrinsic, permeable type. Thus, it is the muscle cell or its basal lamina within muscle grafts that determines the type of surviving vessel. In SCG allografts, even when all their ganglion cells had disappeared, leaving only connective tissue, Schwann cells and their basal lamina, the ganglion's capillaries survived and remained permeable to HRP. Therefore, the characteristics of the SCG vessels are determined by the Schwann cell-fibroblast milieu rather than the neuronal one.
通过三个因素评估循环中的辣根过氧化物酶（HRP）从移植物扩散到脑间质间隙（IS）的效率：移植物类型、部位和年龄。将骨骼肌片、皮肤片或整个颈上神经节（SCG）植入第四脑室（脑室）或脑实质。移植物的年龄，即移植后的间隔时间，分别为1、3、6和12个月。一般来说，HRP从脑室肌和皮肤自体移植物扩散到IS的程度大致相同——1毫米，但从脑实质SCG同种异体移植物扩散的程度较小——0.5毫米。来自所有移植物——脑室和脑实质的扩散都随时间减少。在最初6个月，肌肉的渗出距离与皮肤移植物相同，但到1年时，肌肉的渗透明显大于皮肤移植。在6个月和12个月时，脑实质SCG移植物中HRP的流动比脑实质肌肉和皮肤移植物更广泛。在一些6个月和12个月大的肌肉和皮肤脑实质移植物中，没有检测到HRP外渗。HRP从脑室皮肤和肌肉移植物穿透脑的深度始终比从脑实质移植物更深，因为脑室自体移植物中存活的组织质量比脑实质自体移植物更多。尽管在脑室植入过程中小心避免损伤脑表面，但仍有持续、旺盛的、尚未明确的颅神经侧支发芽。这些新芽支配肌肉和皮肤自体移植物，因此，这些移植物能够存活至少1年，并含有对HRP通透的血管。近交系之间的肌肉同种异体移植物没有被神经支配，仅存活2个月，含有中央屏障型血管，但没有其固有的通透型血管。因此，是肌肉移植物中的肌肉细胞或其基底膜决定了存活血管的类型。在SCG同种异体移植物中，即使所有神经节细胞都消失了，只剩下结缔组织、雪旺细胞及其基底膜，神经节的毛细血管仍存活并对HRP保持通透。因此，SCG血管的特性由雪旺细胞 - 成纤维细胞环境而非神经元环境决定。
