Cell death of primary sensory neurons in the trigeminal ganglion of Brn-3a knockout mice

在Brn-3a野生型和敲除型小鼠胚胎第18.5天和出生后第0天的三叉神经节和口面组织中进行小白蛋白、钙结合蛋白D-28k、calretinin和降钙素基因相关肽的免疫组化。在野生型小鼠中，三叉神经节中含有丰富的小白蛋白、钙结合蛋白D-28k和降钙素基因相关肽免疫反应神经元，而神经节中几乎缺乏钙维素免疫反应神经元。在Brn-3a敲除小鼠中，检测到小蛋白免疫反应神经元减少63%。另一方面，Brn-3a缺失显著增加calbindin D-28k-免疫反应神经元数量（增加3.5倍）和calretinin免疫反应神经元数量（增加91倍）。然而，Brn-3a缺乏并没有改变降钙素基因相关肽免疫反应神经元的数量。细胞大小分析表明，Brn-3a的缺失增加了sm - all （<100 μm^2）小白蛋白-、钙结合蛋白D-28k-…More和降钙素基因相关肽免疫反应神经元的比例，而减少了大（>200 μm^2）免疫反应细胞的比例。突变小鼠calretinin免疫反应神经元为小或中等（100-200 μm^2）。在野生型小鼠的口腔-面部组织中含有细小白蛋白、钙结合蛋白D-28k和降钙素基因相关肽免疫反应纤维，但不含钙蛋白免疫反应纤维。Brn-3a基因敲除小鼠眶下神经中细小蛋白免疫反应纤维数量明显减少，触须中细小蛋白免疫反应末梢消失。另一方面，眼下神经和心神经中calbindin d -28k免疫反应纤维的数量明显增加。此外，在触须中出现calbindin d -28k免疫反应性末梢。在突变体的眶下神经中，一些纤维显示出calretinin免疫反应性。然而，在敲除小鼠的口腔-面部区域未观察到明显的降钙素基因相关肽免疫反应纤维的电荷。综上所述，这些数据表明Brn-3a缺乏对三叉神经节神经化学物质的表达有影响。少

Immunohistochemistry for parvalbumin, calbindin D-28k, calretinin and calcitonin gene-related peptide was performed on the trigeminal ganglion and oro-facial tissues in Brn-3a wildtype and knockout mice at embryonic day 18.5 and postnatal day 0. In wildtype mice, the trigeminal ganglion contained abundant parvalbumin-, calbindin D-28k- and calcitonin gene-related peptide-immunoreactive neurons while the ganglion was almost devoid of calretinin-immunoreactive neurons. In Brn-3a knockout mice, a 63% decrease of parvalbumin-immunoreactive neurons was detected. On the other hand, the absence of Brn-3a dramatically increased the number of calbindin D-28k- immunoreactive (3.5-fold increase) and calretinin-immunoreactive neurons (91-fold increase). The number of calcitonin gene-related peptide-immunoreactive neurons, however, was not altered by the Brn-3a deficiency. Cell size analysis indicated that loss of Brn-3a increased the proportions of sm all (<100 μm^2) parvalbumin-, calbindin D-28k- … More and calcitonin gene-related peptide-immunoreactive neurons while decreased those of large (>200 μm^2) immunoreactive cells. Calretinin-immunoreactive neurons were either small or medium (100-200 μm^2) in mutant mice. The oro-facial tissues contained parvalbumin-, calbindin D-28k- and calcitonin gene-related peptide-immunoreactive fibers but not calretinin-immunoreactive ones in wildtype mice. In Brn-3a knockout mice, the number of parvalbumin-immunoreactive fibers markedly decreased in the infraorbital nerve and parvalbumin-immunoreactive endings disappeared in the vibrissa. On the other hand, the number of calbindin D-28k-immunoreactive fibers increased significantly in the infraorbital and mental nerves. In addition, calbindin D-28k-immunoreactive endings appeared in the vibrissa. As well, some fibers showed calretinin-immunoreactivity In the infraorbital nerve of the mutant. However, no obvious charge of calcitonin gene-related peptide-immunoreactive fibers was observed in the oro-facial region of knockout mice. Taken together, these data suggest that Brn-3a deficiency has effects on the expression of neurochemical substances in the trigeminal ganglion. Less