Estimations of muscle interstitial insulin, glucose, and lactate in type 2diabetic subjects

Citation
M. Sjostrand et al., Estimations of muscle interstitial insulin, glucose, and lactate in type 2diabetic subjects, AM J P-ENDO, 279(5), 2000, pp. E1097-E1103
Citations number
41
Categorie Soggetti
Endocrinology, Nutrition & Metabolism
Journal title
AMERICAN JOURNAL OF PHYSIOLOGY-ENDOCRINOLOGY AND METABOLISM
ISSN journal
01931849 → ACNP
Volume
279
Issue
5
Year of publication
2000
Pages
E1097 - E1103
Database
ISI
SICI code
0193-1849(200011)279:5<E1097:EOMIIG>2.0.ZU;2-O
Abstract
Previous measurement of insulin in human muscle has shown that interstitial muscle insulin and glucose concentrations are similar to 30-50% lower than in plasma during hyperinsulinemia in normal subjects. The aims of this stu dy were to measure interstitial muscle insulin and glucose in patients with type 2 diabetes to evaluate whether transcapillary transport is part of th e peripheral insulin resistance. Ten patients with type 2 diabetes and ten healthy controls matched for sex, age, and body mass index were investigate d. Plasma and interstitial insulin, glucose, and lactate (measured by intra muscular in situ-calibrated microdialysis) in the medial quadriceps femoris muscle were analyzed during a hyperinsulinemic euglycemic clamp. Blood flo w in the contralateral calf was measured by vein plethysmography. At steady -state clamping, at 60-120 min, the interstitial insulin concentration was significantly lower than arterial insulin in both groups (409 +/- 86 vs. 1, 071 +/- 99 pmol/l, P < 0.05, in controls and 584 +/- 165 vs. 1,253 +/- 82 p mol/l, P < 0.05, in diabetic subjects, respectively). Interstitial insulin concentrations did not differ significantly between diabetic subjects and c ontrols. Leg blood flow was significantly higher in controls (8.1 +/- 1.2 v s. 4.4 +/- 0.7 ml . 100 g(-1) . min(-1) in diabetics, P < 0.05). Calculated glucose uptake was less in diabetic patients compared with controls (7.0 /- 1.2 vs. 10.8 +/- 1.2 <mu>mol . 100 g(-1) . min(-1), P < 0.05, respective ly). Arterial and interstitial lactate concentrations were both higher in t he control group (1.7 +/- 0.1 vs. 1.2 +/- 0.1, P < 0.01, and 1.8 +/- 0.1 vs . 1.2 +/- 0.2 mmol/l, P < 0.05, in controls and diabetics, respectively). W e conclude that, during hyperinsulinemia, muscle interstitial insulin and g lucose concentrations did not differ between patients with type 2 diabetes and healthy controls despite a significantly lower leg blood flow in diabet ic subjects. It is suggested that decreased glucose uptake in type 2 diabet es is caused by insulin resistance at the cellular level rather than by a d eficient access of insulin and glucose surrounding the muscle cell.