ATP selectively suppresses the synthesis of the inflammatory protein microglial response factor (MRF)-1 through Ca(2+) influx via P2X(7) receptors in cultured microglia.

Microglia are known to express purinergic receptors for extracellular ATP of both P2Y and P2X subtypes. In the CNS, ATP is released from neurons and acts as a signal between neurons and glia. The mrf-1 gene encodes a 17-kDa protein with a single calcium-binding (EF-hand) motif and is expressed specifically in microglia.