Rothblat D S, Schneider J S
Department of Neurology, Hahnemann University, Philadelphia, PA 19102.
Brain Res Bull. 1994;34(3):309-12. doi: 10.1016/0361-9230(94)90068-x.
Cats exposed to MPTP experience severe motor deficits that spontaneously recover after 4-6 weeks. This recovery occurs despite a persistent deficit (approximately 95%) in dorsal striatal DA levels. To determine whether residual DA neurons that previously did not innervate the dorsal caudate nucleus (CD) have innervated this area in recovered MPTP-treated animals, HRP was injected into the dorsal lateral and dorsal medial CD and the locations of retrogradely labeled neurons in ventral mesencephalon were mapped in normal and recovered MPTP-treated cats. Tyrosine hydroxylase (TH) positive cells were also counted in ventral mesencephalic DA-containing cell groups in normal, symptomatic, and recovered MPTP-treated cats. Results showed no difference in the pattern of HRP labeling in normal and recovered cats except for the loss of labeled substantia-nigra pars compacta (SNc) cells in MPTP-treated cats. Cell counts revealed no significant difference in the degree of TH-positive cell loss in all ventral mesencephalic areas studied in both symptomatic and recovered cats. The results suggest that spontaneous recovery of gross motor function in MPTP-treated cats is most likely not dependent upon reinnervation of the dorsal striatum from residual DAergic neurons.
接触MPTP的猫会出现严重的运动功能障碍，4-6周后会自发恢复。尽管背侧纹状体多巴胺水平持续存在缺陷（约95%），但这种恢复仍会发生。为了确定先前未支配背侧尾状核（CD）的残留多巴胺能神经元在MPTP处理后恢复的动物中是否支配了该区域，将HRP注入背外侧和背内侧CD，并在正常和MPTP处理后恢复的猫中绘制中脑腹侧逆行标记神经元的位置。还对正常、有症状和MPTP处理后恢复的猫的中脑腹侧含多巴胺细胞群中的酪氨酸羟化酶（TH）阳性细胞进行了计数。结果显示，正常猫和恢复猫中HRP标记模式没有差异，只是MPTP处理的猫中标记的黑质致密部（SNc）细胞缺失。细胞计数显示，在有症状和恢复的猫中研究的所有中脑腹侧区域，TH阳性细胞丢失程度没有显著差异。结果表明，MPTP处理的猫的总体运动功能自发恢复最有可能不依赖于残留多巴胺能神经元对背侧纹状体的重新支配。
