Cicchetti F, Parent A
Centre de recherche en Neurobiologie, Hôpital de l'Enfant-Jésus, Québec, Canada.
Mov Disord. 1996 Nov;11(6):619-26. doi: 10.1002/mds.870110605.
The marked atrophy of the striatum seen in Huntington's disease (HD) is largely due to a massive neuronal loss that affects the striatal projection neurons more severely than the local circuit neurons. We recently reported the existence of a new class of interneurons characterized by their immunoreactivity for the calcium-binding protein calretinin in the human striatum. In the present immunohistochemical study, we compared the distribution and relative density of the calretinin-expressing interneurons in the striata of four normal individuals and four patients with HD (grade 1 to 3). The population of calretinin-containing interneurons comprised (a) a small subset of large (17- to 44-microns), multipolar neurons with five to seven long, aspiny, and highly branched dendrites and (b) a large number of medium-sized (8- to 18-microns), round-to-oval neurons with two to three long, varicose, and poorly branched dendrites. Both types of chemospecific neurons occurred throughout the striatum in all specimens examined, but the density of the medium-sized neurons was much higher in patients with HD than in controls. A quantitative analysis showed a significant (p < 0.01) twofold increase in the density of the striatal medium-sized neurons and a similar decrease in the density of the large neurons in patients with HD compared with controls. This differential effect on the densities of the two types of interneurons suggests that calretinin may protect the medium-sized but not the large neurons against neurodegeneration in HD.
在亨廷顿舞蹈症（HD）中所见的纹状体显著萎缩，很大程度上是由于大量神经元丧失，这种丧失对纹状体投射神经元的影响比对局部回路神经元更为严重。我们最近报告了人类纹状体中存在一类新的中间神经元，其特征是对钙结合蛋白钙视网膜蛋白具有免疫反应性。在本免疫组织化学研究中，我们比较了四名正常个体和四名HD患者（1至3级）纹状体中表达钙视网膜蛋白的中间神经元的分布和相对密度。含有钙视网膜蛋白的中间神经元群体包括：（a）一小部分大的（17至44微米）多极神经元，具有五到七个长的、无棘且高度分支的树突；（b）大量中等大小的（8至18微米）圆形至椭圆形神经元，具有两到三个长的、曲张且分支较少的树突。在所有检查的标本中，这两种化学特异性神经元均存在于整个纹状体中，但HD患者中中等大小神经元的密度比对照组高得多。定量分析显示，与对照组相比，HD患者纹状体中中等大小神经元的密度显著增加（p < 0.01），增加了两倍，而大神经元的密度则有类似程度的降低。对这两种中间神经元密度的不同影响表明，钙视网膜蛋白可能保护中等大小神经元而非大神经元免受HD中的神经退行性变。
