Fig. 5

Effect of the H₂S donor, NaSH on FCS-induced activation of extracellular signal–regulated kinase (ERK)–1/2 and p38 mitogen-activated protein kinase (MAPK) in human ASM cells from non-smokers, smokers and COPD patients. ASM cells were incubated with FCS (2.5%) for 1 h and NaSH (100 μM) was added for another 24 h. Total and phospho–ERK-1/2, total and phospho-p38 and β-actin were detected by Western blotting (a), and the corresponding densitometry graphs are shown in b & c. Further examples are shown in Additional file 2: Figure S2. Changes in phospho-MAPK expression were quantitated by densitometry, normalized against β-actin expression, and then expressed as the percent change versus non phosphorylated controls. Bars represent means (± SEM) of nine ASM donors. ^*/+/#P < 0.05; ^**/++/##P < 0.01; ^***/+++/###P < 0.001. **P < 0.01. P-ERK, phosphorylated- ERK; P-p38, phosphorylated p38