Insulin-induced hypoglycaemia was achieved in both hyperglycaemic mice (STZ-T1D+RH: 2.51 ± 0.12 mmol/l [6 weeks], 2.60 ± 0.07 mmol/l [20 weeks]) and control mice (Control+RH: 2.94 ± 0.12 mmol/l [6 weeks], 2.50 ± 0.15 mmol/l [20 weeks]) (Fig. 1c, d). Here, INS is linked to type 1 diabetes mellitus.