Fig. 3.

Effect of the H₂S donor, NaSH on CBS and MPST protein expression 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. CBS, MPST and β-actin were detected by Western blotting (a). Further examples are shown in Additional file 2: Figure S2. Changes in protein expression were quantified by densitometry, normalized against β-actin expression, and then expressed as the percent change versus untreated controls (b & c). Bars represent means (± SEM) of nine ASM donors. ^*/+/#P < 0.05; ^**/++/##P < 0.01; ^***/+++/###P < 0.001