Fig. 2

Relaxant responses of the rat pulmonary artery to SNP (a), BAY 60-2770 (b), and ACh (c). Each point and bar represent the mean ± SEM of six experiments. **p < 0.01, compared with the PBS group. ACh acetylcholine, N(+)-CSE nicotine-containing cigarette smoke extract, N(−)-CSE nicotine-free cigarette smoke extract, PBS phosphate-buffered saline, SNP sodium nitroprusside