Figure 1. SDS-PAGE (8%) analysis of rat cardiac muscle fibre proteins from normal and PTU-treated rat hearts.

Rats were made hypothyroid by feeding with tap water containing 0.6 g l⁻¹ PTU for approximately 4–5 weeks. SDS-PAGE was performed as previously described (Rundell et al. 2004). Lane 1, muscle protein preparation from normal rat heart; lanes 2 and 3, muscle protein preparations from two different PTU-treated rat hearts; lane 4, mixture of normal and PTU-treated rat heart muscle preparations to highlight the size differences between α- and β-MHC isoforms. Lanes 2 and 3 demonstrates a complete shift to β-MHC isoform in PTU-treated rat heart muscle preparations. SDS gels were run at least once and stained with Coomassie blue as described before (Rundell et al. 2004).