Figure 1.

RT-PCR detection of mRNA expression of nicotinic acetylcholine receptor subunits in isolated rat colonic crypts. The agarose gel shows bands of cDNA fragments amplified using primers for α2 (154 bp), α4 (197 bp), α5 (146 bp), α6 (142 bp), α7 (446 bp), α10 (168 bp), β2 (116 bp), and β4 (300 bp). cDNA from spinal cord was used as positive, water instead of cDNA as negative control. The efficiency of RNA isolation and cDNA synthesis was verified by GAPDH-specific primers (303 bp). Each RT-PCR reaction was performed in at least three independent experiments. The mRNA for β2 was only inconsistently detected in two of five experiments, whereas the signals for the other nicotinic receptor subunits depicted here were found consistently. Cry, colonic crypts; SC, spinal cord; RT-PCR, reverse transcription polymerase chain reaction; GAPDH, glyceraldehyde-3-phosphate dehydrogenase.