Lymph flow in the thoracic duct of conscious dogs during lymphatic pump treatment, exercise, and expansion of extracellular fluid volume.
BACKGROUND
This investigation examined interactions between expansion of the extracellular fluid volume (ECE), osteopathic lymphatic pump treatment (LPT), and exercise on lymph flow in the thoracic duct of eight instrumented, conscious dogs.


RESULTS
After recovery from surgery, LPT was performed for 8 min before and after ECE with normal saline, i.v., 4.4+/-0.3% of body weight. Baseline lymph flow was 1.7+/-0.5 mL/min. LPT rapidly increased lymph flow to 5.0+/-1.1 mL/min at 1 min, and lymph flow remained above baseline for 4 min (p<0.05). LPT produced a net increase in lymph flow of 15.4+/-1.1 mL. Following ECE, baseline lymph flow was 4.8+/-0.6 mL/min (p<0.05). LPT increased lymph flow to 9.9+/-1.1 mL/min at 1 min (p<0.05), and lymph flow remained above baseline for 4 min (p<0.05); all flow values after ECE were greater than corresponding values before ECE. However, the net increase in lymph flow produced by 8 min of LPT (18.3+/-3.8 mL) was not significantly greater than that observed before ECE. Moderate treadmill exercise increased lymph flow for 4 min before ECE and for 6 min after ECE. All lymph flows during exercise were greater after ECE than before ECE. The net increase in lymph flow produced by 8 min of exercise was 24.9+/-5.5 mL before ECE and 39.6+/-5.1 mL after ECE (p<0.05).


CONCLUSIONS
Expansion of the extracellular fluid volume produced large increases in thoracic duct lymph flow, that were further augmented by lymphatic pump treatment and by moderate treadmill exercise.
Downey
H Fred
HF
Department of Integrative Physiology, University of North Texas Health Science Center, Fort Worth, Texas 76107, USA. fdowney@hsc.unt.edu
Durgam
Preethi
P
Williams
Arthur G
AG
Rajmane
Amol
A
King
Hollis H
HH
Stoll
Scott T
ST
D000818:Animals; D003243:Consciousness; D004285:Dogs; D045604:Extracellular Fluid / Q000502:physiology*; D006439:Hemodynamics / Q000502:physiology*; D008196:Lymph / Q000502:physiology*; D010805:Physical Conditioning, Animal / Q000502:physiology*; D013897:Thoracic Duct / Q000502:physiology*