The venoarteriolar response of the skin in healthy legs measured at different depths.
The venoarteriolar response (VAR) of the skin in healthy legs of 20 subjects was investigated. The laser Doppler flux (LDF), at an experimental venous hypertension of 30 mmHg, 45 mmHg and 60 mmHg, produced by a pneumatic cuff around the thigh in a recumbent position, was compared with the LDF in a sitting position. The LDF of the skin was measured simultaneously at the same site of the superficial capillary layer (with 543 nm) and of the deeper capillary layer (with 780 nm). At 543 nm the LDF did not differ significantly at any cuff pressure from the LDF recorded in a sitting position, whereas at 780 nm the LDF was significantly higher at the cuff pressure of 30 mmHg than the LDF in a sitting position (P = 0.002). The VAR was much weaker at 543 nm than at 780 nm, and the scatter of the VAR values was high. In a sitting position the VAR at 543 nm was 9.3% and at 780 nm 34.6% (P < 0.001). The VAR at 543 nm at the cuff pressure of 30 mmHg did not differ significantly from the VAR caused by the sitting position, whereas at 780 nm the VAR at the cuff pressure of 30 mmHg was significantly less than the VAR caused by the sitting position (P = 0.001). Despite the high scatter of the VAR values, these findings suggest that the VAR in the superficial capillary layer is smaller, and that it reached maximum at lower venous hypertension, than the VAR in the deeper capillary layer.
Medical Center of Lappeenranta, Finland.
K
K
Malanin
P J
PJ
Kolari
D000328:Adult; D000368:Aged; D001160:Arterioles / Q000502:physiology; D002138:Calibration; D005260:Female; D006801:Humans; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012039:Regional Blood Flow / Q000502:physiology; D012867:Skin / Q000098:blood supply*; D014680:Veins / Q000502:physiology*