Microdialysis measurements in skin: evidence for significant lactate release in healthy humans.
To assess net lactate release from dermal skin, seven lean, healthy men were studied after overnight fasting. Two microdialysis catheters were inserted in the upper dermal tissue, as ensured by ultrasound scanning, in the periumbilical area. Each catheter was calibrated in situ to get an estimate of the lactate concentration in interstitial fluid (1,001 +/- 24 mumol/l), which in turn enabled calculation of the local capillary-venous lactate concentration (963 +/- 25 mumol/l). Concomitantly, arterialized venous plasma lactate (673 +/- 32 mumol/l), blood hematocrit (43 +/- 1%), and skin blood flow (3.8 +/- 0.9 ml.100 g-1.min-1) as measured by 133Xe clearance were determined, and dermal apparent lactate release (570 +/- 89 nmol.100 g-1.min-1) was estimated according to the Fick principle. During an oral glucose tolerance test (OGTT, 75 g), the dermal interstitial-arterial lactate difference decreased significantly to reach a nadir at 60 min. Moreover, no significant increase in skin blood flow was seen during the OGTT. In conclusion, we found a significant net lactate release from abdominal dermal skin after overnight fasting, whereas no significant increase was observed during an OGTT.
Jansson
P A
PA
Lundberg Laboratory for Diabetes Research, Department of Internal Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden.
Krogstad
A L
AL
Lönnroth
P
P
D000328:Adult; D005215:Fasting; D005947:Glucose / Q000494:pharmacology; D005951:Glucose Tolerance Test; D006801:Humans; D007773:Lactates / Q000097:blood / Q000378:metabolism*; D017078:Laser-Doppler Flowmetry; D008297:Male; D017551:Microdialysis; D012016:Reference Values; D012039:Regional Blood Flow; D012867:Skin / Q000098:blood supply / Q000378:metabolism*
D007773:Lactates; D005947:Glucose