AJP - Regulatory, Integrative and Comparative Physiology, Vol 252, Issue 4 782-R785, Copyright © 1987 by American Physiological Society
Thoracic duct lymph flow during head-out water immersion in conscious dogs
K. Miki, M. M. Pazik, E. Krasney, S. K. Hong and J. A. Krasney
Water immersion (WI) increases plasma volume in awake dogs. The
contribution of lymph flow to this fluid shift was studied in six
splenectomized conscious dogs with a side fistula of the thoracic duct.
Lymph flow, hematocrit (Hct), and plasma (CP) and lymph (CL) protein
concentration were measured during 60 min in air and 120 min of WI (37
degrees C). Lymph flow in air averaged 0.96 +/- 1.0 (SE) ml/min. Lymph flow
tended to decrease immediately in WI and was maintained at a level
averaging 0.66 ml/min. CP/CL did not change significantly, whereas Hct fell
significantly by 1.51 +/- 0.2% (Hct units) at 40 min of WI. Urine flow
increased significantly to a maximum value of 1.5 +/- 0.5 ml/min at 40-60
min of WI compared with a mean value in air of 0.3 +/- 0.1 ml/min. The Hct
and urine flow responses indicate that fluid shifted into the intravascular
space during WI. Since lymph flow tended to decrease, the fluid shift in WI
occurs across the capillary wall and not via lymphatic channels.
