Fig. 5.

Activation of MEK1/2 by M3 receptor stimulation is increased in cells adherent to collagen type I. Serum-deprived cells were placed in suspension, and re-plated onto dishes coated with polylysine (pl) or collagen type I (cI). After 2.5 hours, the cells were stimulated with carbachol (100 µM) for 5 minutes or left untreated (control). Nuclear fractions were analyzed by immunoblotting for total MEK1/2 (A) or phospho-MEK1/2 (B). Bands were quantitated by densitometry. Values were normalized to the control/polylysine treatment group (A) or the carbachol/polylysine group (B) and expressed as means ± s.e.m. from 6–9 experiments. *, Significantly different from the corresponding treatment group on polylysine; **, significantly different from the control group on the same substrate.