AJP - Heart and Circulatory Physiology, Vol 261, Issue 6 1970-H1978, Copyright © 1991 by American Physiological Society

ARTICLES

Relationships between lymphatic pump flow and total lymph flow in the small intestine

J. N. Benoit
Department of Physiology and Biophysics, Louisiana State University Medical Center, Shreveport 71130-3932.

Response of collecting lymphatics to acute elevations in lymph formation was studied in vivo. Mesentery of 33 rats was prepared for intravital microscopic study, and indexes of lymph propulsion (contraction frequency, stroke volume, and ejection fraction) were monitored. In 14 rats, total lymph flow was measured by cannulating the main intestinal lymph trunk. After a control period, lymph flow was increased by hemodilution with isotonic saline. Right atrial pressure did not significantly increase during the hemodilution period. Total lymph flow increased to approximately 25 times control. Lymph propulsion (the product of stroke volume and contraction frequency) decreased in five lymphangions (group I). In 22 lymphangions, lymph propulsion increased one to five times control (group II). The remaining six lymphangions increased lymph propulsion by greater than five times control (group III). Group I possessed the largest end-diastolic diameter, highest baseline contraction frequency, and did not dilate as lymphatic filling increased. Group III possessed the smallest initial end-diastolic diameter and lowest baseline contraction frequency, and end-diastolic diameter doubled as lymphatic filling increased. The characteristics of group II were between those of groups I and III. Total lymph flow and lymph propulsion by group III lymphangions tended to agree when lymph flow was less than five times control. In more edematous conditions, total lymph flow exceeded lymphatic pump flow. The characteristics of group II were between those of groups I and III. Analysis of the location of various sized lymphangions within the lymphatic network indicated that the smaller group III lymphangions were located nearer the intestinal wall, and the larger group I lymphangions were nearer the outflow from the mesentery.(ABSTRACT TRUNCATED AT 250 WORDS)

This article has been cited by other articles:

				C. M. Quick, B. L. Ngo, A. M. Venugopal, and R. H. Stewart Lymphatic pump-conduit duality: contraction of postnodal lymphatic vessels inhibits passive flow Am J Physiol Heart Circ Physiol, March 1, 2009; 296(3): H662 - H668. [Abstract] [Full Text] [PDF]

				Y. Shirasawa and J. N. Benoit Stretch-induced calcium sensitization of rat lymphatic smooth muscle Am J Physiol Heart Circ Physiol, December 1, 2003; 285(6): H2573 - H2577. [Abstract] [Full Text] [PDF]

				A. Koller, R. Mizuno, and G. Kaley Flow reduces the amplitude and increases the frequency of lymphatic vasomotion: role of endothelial prostanoids Am J Physiol Regulatory Integrative Comp Physiol, December 1, 1999; 277(6): R1683 - R1689. [Abstract] [Full Text] [PDF]

				K. BULL The Fontan procedure: lessons from the past Heart, March 1, 1998; 79(3): 213 - 214. [Full Text]