EFFECT OF ACUTE MILD HYPOGLYCEMIA ON COUNTERREGULATORY RESPONSES TO MODERATE HYPOGLYCEMIA-INDUCED IMMEDIATELY AFTERWARDS IN HEALTHY-MEN

1. This study was designed to determine whether a 1 h period of mild h ypoglycaemia (3.3 or 3.7 mmol/l) affected the response to an episode o f moderate hypoglycaemia (2.5 mmol/l) immediately afterwards. 2. Eleve n non-obese healthy men (age 26+/-1 years, mean+/-SEM) underwent three separate 3h hyperinsulinaemic glucose clamps in single-blind, random order. On all three occasions, blood glucose was 4.5 mmol/l for the fi rst hour, and on a control visit was maintained at this level for the second hour. In the other two visits, blood glucose was lowered to 3.7 or 3.3 mmol/l during the second hour. In the third hour, blood glucos e was lowered to 2.5 mmol/l on all three visits. 3. In the second hour , adrenaline rose significantly (P<0.05, analysis of variance) with a blood glucose of 3.3 and 3.7 mmol/l, as did cortisol and heart rate at 3.3 mmol/l, but glucagon, prolactin, sweating rate, symptom score and blood pressure were the same during the second hour on all three visi ts. 4. In the final hour at 2.5 mmol/l, there were no differences in a drenaline, noradrenaline, glucagon, prolactin, cortisol, symptom score , heart rate, blood pressure or sweating rate. 5. Thus, the overall ma gnitude of hormonal responses to moderate hypoglycaemia (2.5 mmol/l) a re not modified by exposure to mild hypoglycaemia (3.3 or 3.7 mmol/l) for 1 h immediately beforehand.