Fig. 2.

Nicotine acts through α7 nAChRs. a The absence of α7 nAChR was verified by mRNA and protein expression in the α7KO mice. b α7KO fibroblasts were exposed to nicotine for 24 h and PCR run for collagen type I mRNA expression. Nicotine failed to stimulate collagen type I mRNA expression in α7KO cells. c Nicotine-treated α7KO fibroblasts were subjected to Western blot analysis using anti-collagen type I antibody or GAPDH, followed by secondary goat anti-rabbit IgG (IRDye®). Protein bands were separated by native (collagen type 1) or SDS-PAGE (GAPDH) gel electrophoresis (8%) and quantified by densitometry. Nicotine did not stimulate increased collagen deposition in α7KO fibroblasts. Experiments were repeated at least 3 times. Significance was assessed using p values <0.05 obtained by two-tailed t-test