Department of Molecular Biology, Ariel University Center of Samaria, Ariel, Israel.
Neuropeptides. 2010 Dec;44(6):509-14. doi: 10.1016/j.npep.2010.09.001. Epub 2010 Oct 23.
Pituitary Adenylate Cyclase Activating Polypeptide (PACAP) is a multi-functional neuropeptide that acts through activation of three common G-protein coupled receptors (VPAC1, VPAC2 and PAC1). In this study, we have investigated the gene expression profile of PAC1 isoforms (Hop1, Hip, Hip-Hop) and VPAC1, VPAC2 receptors in distinct brain regions during different stages of rat postnatal development. Using quantitative real time PCR approach we found that PAC1 isoforms were highly expressed in the cortex of newborns with marked decrease in expression during later stages of development. In contrast, mRNA levels of VPAC1, VPAC2 receptors were markedly lower in newborns in comparison to later developmental stages. Expression of PAC1 isoforms predominated in the hippocampus, while expression of VPAC1 was more prominent in the cortex and VPAC2 in the striatum and hippocampus. In addition we found that during early stages of postnatal development the expression of PAC1 receptor in the hippocampus was significantly higher in females than in males. No sex dependent differences in expression were observed for the VPAC1 and VPAC2 receptors. In summary, differential expression of PAC1, VPAC1 and VPAC2 receptors during postnatal development as well as gender dependent differences of PAC1 receptor expression in the hippocampus, will contribute to our understanding of the role of PACAP/VIP signaling system in normal brain development and function.
垂体腺苷酸环化酶激活肽（PACAP）是一种多功能神经肽，通过激活三种常见的 G 蛋白偶联受体（VPAC1、VPAC2 和 PAC1）发挥作用。在这项研究中，我们研究了 PAC1 同工型（Hop1、Hip、Hip-Hop）和 VPAC1、VPAC2 受体在大鼠出生后不同发育阶段不同脑区的基因表达谱。使用定量实时 PCR 方法，我们发现 PAC1 同工型在新生儿皮层中高度表达，在发育后期表达明显下降。相比之下，VPAC1、VPAC2 受体的 mRNA 水平在新生儿中明显低于后期发育阶段。PAC1 同工型在海马中表达占主导地位，而 VPAC1 在皮层中表达更为突出，VPAC2 在纹状体和海马中表达更为突出。此外，我们发现，在出生后的早期发育阶段，雌性大鼠海马中 PAC1 受体的表达明显高于雄性大鼠。VPAC1 和 VPAC2 受体的表达没有性别依赖性差异。总之，PAC1、VPAC1 和 VPAC2 受体在出生后发育过程中的差异表达，以及 PAC1 受体在海马中的性别依赖性表达差异，将有助于我们理解 PACAP/VIP 信号系统在正常大脑发育和功能中的作用。
