Postprandial lymphatic pump function after a high-fat meal: a characterization of contractility, flow, and viscosity

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 Ca2+ 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.

Source: AJP: Gastrointestinal and Liver Physiology - May 14, 2016 Category: Gastroenterology Authors: Kassis, T., Yarlagadda, S. C., Kohan, A. B., Tso, P., Breedveld, V., Dixon, J. B. Tags: NUTRIENT SENSING, NUTRITION, AND METABOLISM Source Type: research