Figure 5. Desmin and vimentin overexpression reduces murine BSM contraction and MLC₂₀ phosphorylation in response to cholinergic agonist.

Murine BSM strips devoid of urothelium and submucosa were transduced with an adenovirus encoding GFP, desmin and vimentin for 48 h and the contractile responses and MLC₂₀ phosphorylation of muscle strips were determined in response to cholinergic agonist. A: Concentration dependent contractile response (cumulative carbachol concentration 10⁻⁹ to 3× 10⁻⁵ M) by murine BSM strips overexpressing GFP, desmin, and vimentin. Data is presented as grams per cross sectional area (g/mm²). B: Concentration dependent contractile response (cumulative carbachol concentration 10⁻⁹ to 3× 10⁻⁵ M) by murine BSM strips overexpressing GFP and uninfected murine BSM strips (without GFP expression). The data is presented as grams per cross sectional area (g/mm²). C-D: Immunoblot analysis of carbachol-stimulated MLC₂₀ phosphorylation in uninfected murine BSM strips and in murine BSM strips overexpressing GFP, desmin or vimentin. BSM strips were contracted for 30 seconds with carbachol (10 μM) and rapidly frozen at 0 sec (resting) and 30 sec of contraction and then the muscle strips were processed for MLC₂₀ phosphorylation. E-F: Quantification of immunoblots (C & D). Data are expressed as means ± standard error mean (SEM), n = 7 mice in each group. **, P ≤ 0.05 versus GFP expressing murine BSM strips in (A). **, P ≤ 0.01 versus murine BSM strips expressing GFP in (E-F).