• Ratio between the plasma glucose level and the glucose concentration at the subcutaneous insulin delivery site [ Time Frame: 1 day ] [ Designated as safety issue: No ]
  

Procedure: OGTT and CLAMP

Oral Glucose Tolerance Test (OGTT):

Oral glucose tolerance test combined with subcutaneous insulin delivery and glucose sampling using a single microdialysis or microperfusion probe.

Hyperinsulinemic euglycemic clamp (CLAMP):

Hyperinsulinemic euglycemic clamp with simultaneous subcutaneous insulin delivery and glucose sampling using microdialysis and microperfusion probe.

Current treatment of in type 1 diabetes comprises the measurement of glucose in capillary blood obtained by fingersticking and administration of exogenous insulin in the form of a subcutaneous bolus injection or subcutaneous infusion. This treatment could be simplified if there were a stable ratio between blood glucose concentration and tissue glucose level at the site of insulin delivery so that tissue glucose levels could be used to estimate blood glucose levels, thereby circumventing the need for fingerstick blood glucose monitoring.

The aim of this study is to ascertain whether a stable ratio between the blood glucose concentration and the glucose levels at the tissue site of insulin infusion exists when this tissue site is exposed to variable insulin infusion rates. To achieve this, microdialysis and microperfusion probes are applied in healthy and type 1 diabetic subjects to perform insulin delivery and glucose sampling at the same adipose tissue site during euglycemic clamps and oral glucose tolerance tests.