INSR and polycystic ovary syndrome: However, Corbould et al. (2005) did not confirm these previous findings in cultured skeletal muscle of obese women with PCOS, showing a decrease in insulin sensitivity in cultured muscle cells from women with PCOS, but normal basal phosphorylation levels as well as normal phosphorylation of tyrosine β-subunit of the insulin receptor after stimulation with insulin [48].