α7 nAChR subunit is expressed in rat microglial cultures. Semiquantitative RT-PCR analysis of α7 nAChR mRNA expression in rat microglial cells (A) and in PC12 cells and rat hippocampus (C). A 754-bp band corresponding to α7 nAChR was specifically amplified (acc. number S53987; amplified region: 906–1660). Expression of β-actin is shown as internal control. No contamination of genomic DNA was present as shown in panel B (-RT: RNA from microglia that was reverse transcribed without the enzyme and amplified for α7 subunit).