Top: Blot of 5-HT-induced (10-9 – 10-5 M) stimulation (30 minutes) 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.