Effects of glucose and insulin levels on adipose tissue glucose measurement by microdialysis probes retained for three weeks in Type 1 diabetic patients.

BACKGROUND

To evaluate the effects of acute hyperglycaemia and hyperinsulinaemia on adipose tissue glucose measurements by microdialysis probes inserted for a 3-week period.

METHODS

Microdialysis probes were implanted pairwise in abdominal adipose tissue in seven Type 1 diabetic patients and remained in situ during the complete study. Stepped hyperglycaemic hyperinsulinaemic clamps were performed at weekly intervals at which the probes were prepared for microdialysis. Adipose tissue glucose by microdialysis was compared to venous and capillary blood glucose concentrations.

RESULTS

The mean time after which the acute rise in blood glucose was first detected was 11.3 min, which corresponds to the system delay of the microdialysis probe. The increase of the glucose concentration in dialysate was completed during the following 16 min. Hyperglycaemia and hyperinsulinaemia did not influence recovery compared to venous blood glucose concentrations, while recovery values compared to capillary blood glucose levels increased slightly under hyperinsulinaemic conditions (P<0.01).

CONCLUSIONS

In Type 1 diabetic patients, recovery of glucose in adipose tissue compared to venous and capillary blood does not decrease during acute hyperglycaemia and hyperinsulinaemia. Although there is still a relevant time-delay to monitor a rise in blood glucose, these results show that microdialysis may offer an opportunity for future glucose monitoring over a prolonged time-period.