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

在胚胎第18.5天和出生后第0天，对Brn-3a野生型和敲除小鼠的三叉神经节和口面部组织进行小清蛋白、钙结合蛋白D-28 k、钙视黄蛋白和降钙素基因相关肽的免疫组织化学。在野生型小鼠中，三叉神经节含有丰富的小白蛋白，钙结合蛋白D-28 k和降钙素基因相关肽免疫反应神经元，而神经节几乎没有钙视黄蛋白免疫反应神经元。在Brn-3a基因敲除小鼠中，检测到小清蛋白免疫反应性神经元减少63%。另一方面，Brn-3a的缺乏显著增加了钙结合蛋白D-28 k免疫反应性神经元（增加3.5倍）和钙视黄蛋白免疫反应性神经元（增加91倍）的数量。然而，降钙素基因相关肽免疫反应神经元的数量没有改变Brn-3a缺乏。细胞大小分析表明，Brn-3a的缺失增加了小白蛋白（<100 μm^2）、钙结合蛋白D-28 k- ...更多信息 降钙素基因相关肽免疫反应阳性神经元减少，而大细胞（>200 μm^2）免疫反应阳性神经元减少。在突变小鼠中，钙视黄蛋白免疫反应阳性神经元为小型或中型（100-200 μm^2）。口面部组织中含有小白蛋白，钙结合蛋白D-28 k和降钙素基因相关肽免疫反应性纤维，但在野生型小鼠中没有钙视黄蛋白免疫反应性纤维。Brn-3a基因敲除小鼠眶下神经小清蛋白阳性纤维明显减少，触须小清蛋白阳性终末消失。另一方面，在眶下神经和颏神经中，钙结合蛋白D-28 k免疫反应阳性纤维的数量显著增加。此外，在触须中还出现了钙结合蛋白D-28 k免疫反应阳性的终末。此外，一些纤维显示钙视网膜蛋白免疫反应在眶下神经的突变体。然而，没有明显的电荷降钙素基因相关肽免疫反应纤维观察到在口面部区域的基因敲除小鼠。总之，这些数据表明，Brn-3a缺乏对三叉神经节中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