Figure 3.

p38 kinase is bidirectionally regulated by 5-HT and FMRFa. Treatment with FMRFa (9 μm, 10 min) increased the phosphorylation of p38 kinase in pleural ganglion neurons, and treatment with 5-HT (50 μm, 10 min) decreased the phosphorylation. As control, the total amount of kinase was detected by immunoblotting with anti-Ap-p38 kinase. A, Representative immunoblots from four independent experiments are shown. B, Group data showing the regulation of phosphorylation by the two transmitters. Treatment with FMRFa stimulated the phosphorylation of p38 kinase, and 5-HT diminished the phosphorylation. The ratio of phospho-p38 kinase to the nonphosphorylated form was determined in each group of four experiments. The bars represent the mean values obtained with each transmitter divided by the contral ratio. Asterisks indicate significance p < 0.05.