Preprotachykinin-A and substance P receptor (NK1) gene expression in rat astrocytes in vitro.

The presence of mRNA transcripts coding for preprotachykinin-A and the substance P receptor in cultured astrocytes is demonstrated by a combination of reverse transcription/polymerase chain reaction (PCR) and Southern blotting. These findings showed that astrocytes in culture are capable of synthesing both the precursor of substance P (preprotachykinin-A) and the cognate receptor, substance P receptor (NK1). The simultaneous presence of both the ligand (substance P) and the receptor (NK1) may indicate an autocrine nature of astrocyte communication.