INS and diabetes mellitus: However Defronzo’s original hyperinsulinaemic study showed that insulin concentration reach a steady state after 20 minutes [33] and Middelbeek et al have shown that Akt Thr308 and AS160 phosphorylation was similar in biopsies taken at 30 minutes and 180 minutes into a hyperinsulinaemic clamp study in lean and obese patients with and without diabetes [34].