Non-asthmatic ASM cells were treated with either 20ng/ml TNFα or 50ng/ml IL-13 for 24h or 48h before total RNA was isolated and reverse transcribed. The resultant cDNA was subjected to qPCR to measure the expression of various ERβ isoforms. (A) While a 24h TNFα treatment increases the expression of ERβ variants 1, 2 and 4, there was no quantifiable change in ERβ variant 5 expression; interestingly, ERβ variant 3 expression was downregulated by this treatment. On the other hand, expression of variants 1, 2, 4 and 5 respond positively to a 24h IL-13 treatment while the variant 3 expressions remain unaffected. (B) The trend changes 48h post treatment: expression of all 5 isoforms increases after a 48h treatment with TNFα, while IL-13 treatment upregulates variants 1–4 but not variant 5. N=4, each group; *indicates significant difference from vehicle; P<0.05.