Glucose clamp technique

Glucose clamp technique is used to measure either how well an individual metabolizes glucose or how sensitive an individual is to insulin. Two types of clamps are quite commonly used.

The hyperglycemic clamp, which requires maintaining a high blood sugar level by perfusion or infusion with glucose, is a way to quantify how fast beta-cells respond to glucose.

The hyperinsulinemic clamp, which requires maintaining a high insulin level by perfusion or infusion with insulin, is a way to quantify how sensitive the tissue is to insulin.

Hyperglycemic clamp technique:
Glu raised to 125 mg/dl above basal levels by a continuous infusion of glucose. The glucose infusion rate is an index of insulin secretion and glucose metabolism. The hyperglycemic clamps are often used to assess insulin secretion capacity.

Hyperinsulinemic-euglycemic clamp technique:
The plasma insulin concentration is acutely raised and maintained at 100 μU/ml by a continuous infusion of insulin. The plasma glucose concentration is held constant at basal levels by a variable glucose infusion. When the steady-state is achieved, the glucose infusion rate equals glucose uptake by all the tissues in the body and is therefore a measure of tissue insulin sensitivity. The hyperinsulinemic clamps are often used to measure insulin resistance.