Human and porcine insulins are equally effective in the regulation of glucose kinetics of diabetic patients during exercise.

The rate of hepatic glucose production (Ra) and peripheral utilization (Rd) was determined in 8 insulin-dependent diabetic subjects in basal state and during 40 min cycle ergometric exercise. The patients were treated with continuous sc infusion of either semisynthetic human or porcine (Actrapid) insulin. Basal rate of glucose production was comparable during human (2.29 +/- 0.19 mg/kg/min) and porcine (2.18 +/- 0.12 mg/kg/min) insulin therapy. In response to exercise, Ra rose 30 to 40% (P less than 0.05), to 2.85 +/- 0.35 vs 3.18 +/- 0.42 mg/kg/min, similarly during both studies. The peak rise in Rd (to 3.20 +/- 0.32 during human vs 3.78 +/- 0.44 mg/kg/min during porcine insulin) was comparable in both groups and not significantly different from the rise in Ra. Consequently, blood glucose levels remained unchanged. During the exercise tests, the metabolic conditions were stable and comparable in both studies, as indicated by similar levels of blood glucose, plasma free insulin HbA1, serum lipids and insulin binding to erythrocytes. In conclusion, semisynthetic human insulin is equally effective as porcine insulin in regulating glucose kinetics in the basal state and during exercise.