Oligodendrocytes express functional A1 adenosine receptors that stimulate cellular migration

A1 adenosine receptors (A1ARs) exert important effects in the central nervous system. However, the expression and function of A1ARs in oligodendrocyte precursor cells (OPCs) and oligodendrocytes (OLGs) is unclear. To address this issue, we examined A1AR expression during different stages of oligodendrocyte development. Radioreceptor studies showed that membranes prepared from OPCs and OLGs expressed high-affinity A1ARs with K-d values of 1.35 +/- 0.33 and 1.2 +/- 0.27 nM for [H-3]CCPA, 1.17 +/- 0.24 and 1.4 +/- 0.34 nM for [H-3]DPCPX, respectively. B-max values were 64.31 +/- 6.14 and 75 +/- 6 fmol/mg protein for [H-3]CCPA, and 153 +/- 12 and 205 +/- 17.8 fmol/mg protein for [H-3]DPCPX, respectively. Activation of A1ARs using N-6-cyclo-pentyladenosine (CPA) reduced both forskolin- and N-ethylcarboxyamidoadenosine (NECA)-stimulated cAMP accumulation, but did not affect basal cAMP levels. Activation of A1ARs by CPA stimulated OPC migration, but did not affect cell viability, proliferation, or differentiation. These results show that OPCs and OLGs express functional A1ARs that can stimulate the migration of OPCs. (C) 2003 Wiley-Liss, Inc.