Flow velocity of single lymphatic capillaries in human skin. Fischer, Matthias, Ulrich K. Franzeck, Ines Herrig, Umberto Costanzo, Shenghua Wen, Monika Schiesser, Ulrich Hoffmann, and Alfred Bollinger. Department of Internal Medicine, Angiology Division, University Hospital, CH-8091 Z[umlaut]urich, Switzerland
APStracts 2:0290H, 1995.
Purpose of the study was to investigate the previously unknown flow velocity in single human lymphatic capillaries in supine position. Fifteen healthy volunteers (10 women, 5 men; mean age 35.8 +/- 13.1 years) were studied. FITC-dextran 150'000 (10 [mu]l) was injected into the subepidermal layer of the foot dorsum. The filling of the microlymphatics from the resulting depot was visualized by fluorescence videomicroscopy and stored on videotape. Flow velocity in the microlymphatics was determined on the videoscreen by direct measurement of the advancement of dye filled lymph during a given time. The following median velocities were obtained: 0.51 mm/s (lower quartile 0.27 mm/s, upper quartile 0.61 mm/s) for velocity during initial network filling and 9.7 [mu]m/s (lower quartile 6.9 [mu]m/s, upper quartile 14.2 [mu]m/s) for resting velocity at the end of the filling period. Mean lymphatic capillary diameter was 54.8 +/- 8.2 [mu]m, mean network extension 8.3 +/- 3.2 mm. The high filling velocities are probably due to increased interstitial pressure and volume caused by dye microinjection, whereas the values measured during the end of network filling seem to approach resting flow velocities. 

Received 20 December 1994; accepted in final form 24 April 1995.
APS Manuscript Number H1116-4.
Article publication pending Am. J. Physiol. (Heart Circ. Physiology).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 18 July 1995.