A morphological study of the brain in the ataxic mutant rat.

一种共济失调突变大鼠，稀释-斜纹肌（dop），最初是在Wister大鼠的繁殖群体中发现的，它表现出毛色稀释和神经障碍，伴有抽搐肢体运动和斜纹肌痉挛发作，直到动物在3周龄时死亡。这些动物是在我们实验室通过杂合大鼠杂交繁殖的。利用pcr扩增的微卫星标记在8号染色体上定位了稀释-opisthotonus基因，发现该突变与Apoc3、dopp和Mylclv基因连锁，表明该突变与小鼠稀释-lethalof同源。电镜和免疫细胞化学检测结果显示，浦肯野细胞树突棘缺失光滑内质网（SER）。对发育中的浦肯野细胞的观察表明，SER在浦肯野细胞的体细胞和树突中形成，而在脊柱中不形成。SER被认为是细胞内的钙储存，并且已经提出突触部位的钙信号传导过程在突触传递中起关键作用。因此，大鼠被认为突触调节受损。电镜和免疫细胞化学检测结果显示，浦肯野细胞轴突末端与小脑深部核内神经元的接触正常。

An ataxic mutant rat, dilute-opisthotonus (dop), was originally discovered in a breeding colony of Wister rats and shows a dilution of coat color and neurological disorders with convulsivelimb movements and opisthotonic seizures continuing until the death of animals at 3 weeks of age. The animals have been bred in our laboratory by intercrossing the heterozygous (dop/+) rats. The dilute-opisthotonus gene was mapped on chromosome 8 by PCR-amplified microsatellite markers, which showed a linkage of Apoc3, dop and Mylclv genes, suggesting that this mutation was homologous to dilute-lethalof the mouse.Electronmicroscopy and immunocytochemistry using anti-inositol 1,4,5-triphosphate (InsP3) receptor antibody revealed that smooth endoplasmic reticulum (SER) was missing in the dendritic spine of Purkinje cell in the dop cerebellum. Observation of developing Purkinje cells showed that SER was formed in the soma and dendrites but not in the spine of the Purkinje cell.SER is assumed to be an intracellular Ca store and it has been suggested that a Ca signaling process at the synaptic site has a key role in synaptic transmission. Thus, the dop rat is thought to have impaired synaptic regulation. Electronmicroscopy and Immunocytochemistry using antibody raised against GABA,transmitter released by Purkinje cell terminals, indicated that Purkinje cell axon terminals normally contacted the neurons in deep cerebellarnuclei.