Fig. 3.

Effect of cAMP on MAPK activation in human T lymphocytes and role of PKA in this effect. Cells were stimulated for 20 min with the indicated doses of cptcAMP. MAPK activation was assessed by Western blotting. (A) P-ERK, ERK, P-JNK and JNK in T lymphocytes stimulated with 250 µM of cptcAMP. (B) P-p38 and total p38 in T lymphocytes stimulated with increasing doses (25, 250 and 500 µM) of cptcAMP. (C) P-p38 and total p38 in T lymphocytes preincubated for 2 h with increasing doses of H89, before stimulation with cptcAMP (250 mM). The results in A-C are obtained from three different donors. The results in B are obtained from the same donor as in figure 5A.