Fig. 5.
Effect of nicotine on Bcl-2, p53, and caspase-3 protein levels. (A) Cells were subjected to Western blot analysis after 10−2 M nicotine treatment for various amounts time (0–120 min) and then phosphorylation of p53 was determined. (B) Cells were treated with nicotine (0–10−2 M) for 48 h then the protein levels of Bcl-2, p53, and cleaved caspase-3 were assessed using total protein lysates. The panels (bars) denote the mean ± S.D. of five experiments for each condition determined from densitometry relative to β-actin. *P < 0.05 or #P < 0.001 vs. control value. (C) Cells were pretreated with each α-BTX or mecamylamine for 1 h before the addition of 10−2 M nicotine. After 48 h of incubation, each apoptotic signal protein was analyzed.