Analysis of neuropeptide PACAP receptor positive stromal cells in thymus

垂体腺苷环化酶激活多肽(PACAP)是一种多功能、多效性的信号分子，具有重要的免疫相关活性。我们先前报道，PACAP受体(PAC1-R)在大鼠胸腺髓质中强表达，并且其表达受辐射的影响。在这项研究中，我们对大鼠胸腺中的PAC1-R阳性细胞进行了详细的研究，并对恒河猴胸腺细胞进行了检测，TCDD是一种已知的损害胸腺和T细胞的化学物质。在大鼠胸腺中，PAC-1-R阳性细胞位于胸腺髓质的中间型上皮细胞中。PAC1-R阳性细胞也见于恒河猴胸腺髓质。在一些恒河猴母猴和暴露于TCDD的后代中，胸腺显示出不寻常的结构。此外，在这些恒河猴中，PAC1-R的表达与对照胸腺不同。PACAP已被报道可减轻大鼠缺血性神经元损伤，增加IL-6的分泌。我们还研究了PACAP和IL-6在介导脑缺血后神经保护中的作用。我们的结果表明，PACAP通过涉及IL-6的信号机制来防止缺血后神经细胞的死亡。

Pituitary adenylate cyclase-activating polypeptide (PACAP) is a multifunctional and pleiotropic signal molecule with important activities related to immunity. We previously reported that the PACAP receptor (PAC1-R) is strongly expressed in storomal cells in the medulla of the rat thymus and that its expression in affected by irradiation. In this study we present a detailed investigation of PAC1-R-positive cells in the rat thymus and examine thymus cells of rhesus monkeys TCDD a chemical known to impair thymus and T cells.In the rat thymus, PAC-1-R-positive cells were found in the intermediate type of thymic epithelial cells of the medulla. PAC1-R-potive cells were also seen in the thymic medulla of the rhesus monkey. The thymus showed unusual structures in some rhesus monkey dams and offspring exposed TCDD. Additionally, in these rhesus monkeys, PAC1-R expression was different from that in the control thymus.PACAP has been reported to decrease ischemic neuronal damage and increase IL-6secretion in rats. We also investigated the role played by PACAP and IL-6 in mediating neuroprotection after ischemia. Our results suggest that PACAP prevents neuronal cell death after ischemia via a signaling mechanism involving IL-6.