title: Postprandial lymphatic pump function after a high-fat meal: a characterization of contractility, flow, and viscosity.
abstract: Dietary lipids are transported from the intestine through contractile lymphatics. Chronic lipid loads can adversely affect lymphatic function. However, the acute lymphatic pump response in the mesentery to a postprandial lipid meal has gone unexplored. In this study, we used the rat mesenteric collecting vessel as an in vivo model to quantify the effect of lipoproteins on vessel function. Lipid load was continuously monitored by using the intensity of a fluorescent fatty-acid analog, which we infused along with a fat emulsion through a duodenal cannula. The vessel contractility was simultaneously quantified. We demonstrated for the first time that collecting lymphatic vessels respond to an acute lipid load by reducing pump function. High lipid levels decreased contraction frequency and amplitude. We also showed a strong tonic response through a reduction in the end-diastolic and systolic diameters. We further characterized the changes in flow rate and viscosity and showed that both increase postprandially. In addition, shear-mediated Ca(2+) signaling in lymphatic endothelial cells differed when cultured with lipoproteins. Together these results show that the in vivo response could be both shear and lipid mediated and provide the first evidence that high postprandial lipid has an immediate negative effect on lymphatic function even in the acute setting.
authors.affiliation: Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, Atlanta, Georgia; School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, Georgia;
authors.forename: Timothy
authors.initials: T
authors.lastname: Kassis
authors.affiliation: School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia; and.
authors.forename: Sri Charan
authors.initials: SC
authors.lastname: Yarlagadda
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio.
authors.forename: Alison B
authors.initials: AB
authors.lastname: Kohan
authors.affiliation: Department of Pathology and Laboratory Medicine, University of Cincinnati, Cincinnati, Ohio.
authors.forename: Patrick
authors.initials: P
authors.lastname: Tso
authors.affiliation: School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia; and.
authors.forename: Victor
authors.initials: V
authors.lastname: Breedveld
authors.affiliation: Parker H. Petit Institute for Bioengineering & Bioscience, Georgia Institute of Technology, Atlanta, Georgia; George W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia; dixon@gatech.edu.
authors.forename: J Brandon
authors.initials: JB
authors.lastname: Dixon
mesh_terms: D000818:Animals; D020013:Calcium Signaling; D002478:Cells, Cultured; D004041:Dietary Fats / Q000378:metabolism*; D042783:Endothelial Cells / Q000378:metabolism; D006801:Humans; D008196:Lymph / Q000378:metabolism / Q000502:physiology; D042601:Lymphatic Vessels / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D008297:Male; D009119:Muscle Contraction; D009130:Muscle, Smooth / Q000502:physiology; D019518:Postprandial Period; D051381:Rats; D017207:Rats, Sprague-Dawley; D014783:Viscosity
chemical_list: D004041:Dietary Fats
keywords: chylomicron; lipid absorption; lymphatic; pump function; viscosity