Fig. 3. Parietal stressed is associated with a selective increase phosphorylated MAPK ERK and JNK but not p38 in urothelial cells. Western blot analysis of freshly scraped urothelial cells using specific antibodies against the phosphorylated and the non phosphorylated form of the MAPKs p38 (A), ERK (B), JNK (C) demonstrates an increase in the phosphorylated form of the MAPKs ERK and JNK but not in p38 in urothelium of dilated bladder after seven hours of obstruction, compared with empty bladder. Each lane is from a different animal and quantitative assessment of five experiments (one per rat) confirmed that the levels of P-JNK and P-ERK were increased six-fold and four-fold respectively over control values. Values represent ratios of densitometric measurements of either P-JNK or JNK, P-ERK and ERK or P-p38 and p38 and are expressed as mean±s.e.m.