Florenzano F, Carrive P, Viscomi M T, Ferrari F, Latini L, Conversi D, Cabib S, Bagni C, Molinari M
Istituto di Ricovero e Cura a Carattere Scientifico (I.R.C.C.S.) Santa Lucia Foundation, Via Fosso del Fiorano 64, Rome, Italy.
Neuroscience. 2008 Feb 6;151(3):791-801. doi: 10.1016/j.neuroscience.2007.11.027. Epub 2007 Nov 29.
Ionotropic purinergic receptors (P2XR) are ATP-gated cationic channels composed of seven known subunits (P2X(1-7)R) and involved in different functions in neural tissue. Although their presence has been demonstrated in the brain, few studies have investigated their expression pattern. In particular, ionotropic purinergic receptor subunit type 1 (P2X(1)R) has been observed in the cerebellum and in brainstem nuclei. The present study investigates the P2X(1)R expression pattern in the rat forebrain using immunohistochemistry. The specificity of the immunolabeling has been verified by Western blotting and in situ hybridization methods. P2X(1)R immunoreactivity was specifically localized in neurons, dendrites and axons throughout the forebrain. Characteristic differences in the distribution of P2X(1)R were observed in different cortical areas. In prefrontal, cingulate and perirhinal cortices, very intense labeling was present in neuronal bodies. In frontal, parietal, temporal and occipital cortices, immunostaining was lighter and mainly found in dendrites and axons. The hippocampal formation was intensely labeled. Labeling was present almost exclusively in dendrites and axons and never in neuronal bodies. The diencephalon was devoid of P2X(1)R positive neurons or fibers except for the medial habenular nucleus, which showed very intense P2X(1)R immunostaining. Furthermore, two subcortical regions, namely, the nucleus centralis of the amygdala and the bed nucleus of the stria terminalis, showed intense P2X(1)R neuronal labeling. Present data indicate that P2X(1)R are prevalent in forebrain areas involved in the integration of cognitive, limbic and autonomic functions.
离子型嘌呤能受体（P2XR）是由七个已知亚基（P2X(1 - 7)R）组成的ATP门控阳离子通道，参与神经组织的不同功能。尽管它们在大脑中的存在已得到证实，但很少有研究调查其表达模式。特别是，离子型嘌呤能受体1型（P2X(1)R）已在小脑和脑干核中被观察到。本研究使用免疫组织化学方法研究大鼠前脑中P2X(1)R的表达模式。免疫标记的特异性已通过蛋白质印迹法和原位杂交法进行验证。P2X(1)R免疫反应性特异性地定位于整个前脑的神经元、树突和轴突中。在不同的皮质区域观察到P2X(1)R分布的特征性差异。在额叶前部、扣带回和梨状周围皮质中，神经元胞体中存在非常强烈的标记。在额叶、顶叶、颞叶和枕叶皮质中，免疫染色较浅，主要见于树突和轴突。海马结构被强烈标记。标记几乎仅存在于树突和轴突中，从未见于神经元胞体。除了内侧缰核显示非常强烈的P2X(1)R免疫染色外，间脑没有P2X(1)R阳性神经元或纤维。此外，两个皮质下区域，即杏仁核中央核和终纹床核，显示出强烈的P2X(1)R神经元标记。目前的数据表明，P2X(1)R在前脑参与认知、边缘和自主功能整合的区域中普遍存在。
