Top: Blot of 5-HT-induced (10-5 M) stimulation (5 min, 15 min, 30 min and 60 min) of the JNK pathway in rat aortic vascular smooth muscle cells as measured by use of a phosphospecific JNK antibody. Blot is representative of four experiments. Middle: Total anti-JNK antibody recognizes nonphosphorylated forms as well as phosphorylated protein. Bottom: Densitometry measurements are for the 46 kDa band. Bar graphs represent means and vertical bars the SEM for N = 4. * = statistical difference for response in vehicle-incubated cell cultures.