Structural organization of the main olfactory bulb: further analysis of juxtaglomerular neurons

小鼠主嗅球（MOB）中的小球旁神经元（JG）由多种类型的神经元组成。在本研究中，我们研究了(1)分泌素（SCGN）阳性神经元的结构特征，(2)两种转录因子Sp8和Tbx21在JG神经元亚群中的表达。scgn阳性神经元遍布各层，分布不均，包括JG神经元、颗粒细胞等。在形态学上，JG scgn阳性神经元部分为典型的肾小球周围细胞（PG），而另一些则与PG细胞有明显差异。一些延长一个细长的过程成为肾小球，通过肾小球并进一步渗透到附近的另一个肾小球。我们将这种类型的JG神经元命名为经肾小球细胞。Sp8和Tbx21的免疫反应性在染色强度上差异很大。Sp8和Tbx21的免疫反应进一步表征了JG神经元的特征，尤其证实了NOS阳性JG神经元的异质性。

Juxtaglomerular (JG) neurons in the mouse main olfactory bulb (MOB) consist of various types of neurons. In the present study we examined (1) the structural features of secretagogin(SCGN)-positive neurons, and (2) The expressions of two transcription factors, Sp8 and Tbx21, in the JG neuronal subpopulations.SCGN-positive neurons were localized throughout layers, and heterogeneous, including JG neurons, granule cells, et al. Morphologically some of JG SCGN-positive neurons were classical periglomerular (PG) cells, whereas others were apparently different from those PG cells. Some extended one slender process into a glomerulus which passed the glomerulus and further penetrated into another nearby glomeruli. We named this type of JG neurons, transglomerular cells. Both Sp8 and Tbx21 immunoreactivities were so diverse in their staining intensities. Sp8 and Tbx21 immunoreactivities further characterized JG neurons and, especially confirmed the heterogeneity of NOS positive JG neurons.