Figure 1.

Expression of nicotinic acetylcholine (ACh) receptor (nAChR) in monkey cultured bronchial epithelial cells (BECs) and in vivo. BECs were cultured as described in Materials and Methods. (A) Confirming their identity, cultured BECs expressed cytokeratin (4 d in culture). Calibration bar represents 90 μm. (B–D) The α7, α4, and β2 nAChR subunits were observed in lung sections (insets: lack of staining in absence of primary antibody). Calibration bars represent 35 μm. (E, a), α7 nAChR expression in cultured BEC; (E, b) α7 nAChR expression in cultured BECs incubated with 1 μM nicotine for 48 hours. (F) RT-PCR showed the presence of α3, α4.1, α7, α9, α10, β2, and β4 nAChR mRNAs in cultured BECs. Monkey hypothalamus (Hypo) was included as positive control. No bands were seen in negative controls (water), which lacked input RNA.