Nori S, Fumagalli L, Bo X, Bogdanov Y, Burnstock G
Department of Anatomy and Developmental Biology, University College London, UK.
J Vasc Res. 1998 May-Jun;35(3):179-85. doi: 10.1159/000025582.
The expression of mRNAs for three P2X receptor subtypes (PX21, P2X2, P2X4) in the rat vascular system was studied by in situ hybridization and RT-PCR. In heart sections mRNAs transcripts for all three receptors were colocalized in smooth muscle cells of coronary vessels, while no specific positivity was apparent in myocardium. Coexpression of P2X receptor mRNA transcripts were also observed in other peripheral vessels, including aorta, pulmonary artery, internal and external iliac arteries, renal artery and femoral artery. By contrast, no mRNA transcripts of the above receptors were found in the superior mesenteric artery. RT-PCR performed on microdissected tissues (coronary arteries, aorta and myocardium from various heart areas) confirmed the presence of P2X1, P2X2 and P2X4 receptor mRNAs. Furthermore, in the same tissues two splice variants of the P2X2 receptor were identified. These results reveal an important molecular heterogeneity of P2X receptors, thus substantiating the possibility of a heteropolymeric assembly of ATP-gated ion channels in the cardiovascular system.
通过原位杂交和逆转录聚合酶链反应（RT-PCR）研究了大鼠血管系统中三种P2X受体亚型（P2X1、P2X2、P2X4）的mRNA表达。在心脏切片中，所有三种受体的mRNA转录本共定位于冠状血管的平滑肌细胞中，而心肌中未观察到特异性阳性信号。在其他外周血管，包括主动脉、肺动脉、髂内动脉、髂外动脉、肾动脉和股动脉中也观察到P2X受体mRNA转录本的共表达。相比之下，在肠系膜上动脉中未发现上述受体的mRNA转录本。对显微切割组织（来自不同心脏区域的冠状动脉、主动脉和心肌）进行的RT-PCR证实了P2X1、P2X2和P2X4受体mRNA的存在。此外，在相同组织中鉴定出了P2X2受体的两种剪接变体。这些结果揭示了P2X受体重要的分子异质性，从而证实了心血管系统中ATP门控离子通道异聚体组装的可能性。
