The regulation of lymphatic pumping.
An important functional property of lymphatic vessels is their ability to pump fluid. To quantitate this activity in vivo, sheep mesenteric lymphatic segments were isolated from all lymph input and provided with lymph plasma or saline from a reservoir. Lymphatic pumping was controlled by transmural pressure with increases in pressure resulting in elevated fluid pumping followed by reductions in flow at high intraluminal pressures. With lymph input to the vessels denied, but with blood and nerve supply left intact, the pumping activity could be altered with systemic physiological perturbations including a major blood loss and the intravenous infusion of endotoxin. In each case, it was clear that the modulation of lymphatic pumping resulted from the direct effects of the test procedure on the 'lymph pump' and not from effects on vascular parameters or lymph formation.
Johnston
M G
MG
Department of Pathology, University of Toronto, Ontario, Canada.
Elias
R
R
D000818:Animals; D004731:Endotoxins / Q000633:toxicity; D008208:Lymphatic System / Q000187:drug effects / Q000502:physiology*; D011673:Pulsatile Flow / Q000187:drug effects; D012756:Sheep
D004731:Endotoxins