Cellular distribution of the P2X(4) ATP receptor mRNA in the brain and non-neuronal organs of rats

RNA blot analysis has shown that an ionotropic ATP receptor P2X(4) is widely distributed, as compared with other P2X subtypes. Cellular distribution of the P2X(4) ATP receptor mRNA was investigated by in situ hybridization technique in the brain and non-neuronal organs, In the brain, transcripts of the P2X(4) were widely distributed in various regions, with the highest signals in the cerebellar Purkinje cells and granule cells. In other organs, intense and selective expression a-as detected in seminiferous tubules of the testis and intestinal crypts of the colon, suggesting an involvement of ATP in spermatogenesis and intestinal secretion. A low but significant level of the P2X(4) mRNA was detected in the adenohypophysis and the cortex of the adrenal gland. The tissue- or cell-specific expression of the P2X(4) mRNA is of importance to understand the functional roles of the purinergic transmission system.