Improved Glucose Disappearance Following Repeated Glucose Administration: Serum Insulin, Growth Hormone and Free Fatty Acid Levels During the Staub-Traugott Effect

Abstract

The Staub-Traugott effect, the phenomenon of improved tolerance to repeated glucose administration, was investigated in fifteen healthy volunteers. Two glucose loads were administered intravenously forty-six minutes apart. Blood samples were taken periodically after each glucose infusion. The second glucose load was given immediately after the first sampling period. The glucose disappearance rate (K) improved after the second infusion from 2.04 ± 0.23 to 2.87 ±0.16 (p < 0.001). Serum immunoreactive insulin levels rose promptly after the glucose infusions, but while a decrease was noted following the first peak, the levels remained persistently elevated after the second glucose load. Growth hormone levels decreased and were slightly lower yet six to nine minutes after completion of the infusions. A striking reduction of free fatty acid levels followed the first glucose load; values fell to 50 per cent of the fasting levels prior to, and decreased even further following, the second infusion. Thus, the improved K of the second glucose tolerance test was associated with already diminished serum free fatty acid levels.