Glucose Levels at the Site of Subcutaneous Insulin Administration and Their Relations

[Sysop]

Objective:To examine insulin's effect on the tissue glucose concentration at the site of subcutaneous insulin administration.
Research Design And Methods:A CMA-60 microdialysis (MD) catheter and a 24-gauge microperfusion (MP) catheter were inserted into the subcutaneous adipose tissue of fasting, healthy subjects (n=5). Both catheters were perfused with regular human insulin (100 U/ml) over a 6-h period, and used for glucose sampling and simultaneous administration of insulin at sequential rates of 0.33, 0.66, and 1.00 U/h (each rate was used for 2h). Before and after the insulin delivery period, both catheters were perfused with an insulin-free solution (5%-mannitol) for 2h, and used for glucose sampling only. Blood plasma glucose was clamped at euglycemic levels during insulin delivery.
Results:
Start of insulin delivery with MD and MP catheters resulted in a decline of the tissue glucose concentration and the tissue-to-plasma glucose ratio for ~60 min (p