Premium
Nitric Oxide Production By Contracting Rat Mesenteric Lymphatic Vessels Is Primarily Within Valvular Regions
Author(s) -
Bohlen Harold Glenn,
Gasheva Olga,
Gashev Anatoliy,
Zawieja David
Publication year - 2008
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.22.1_supplement.1141.6
Subject(s) - lymphatic system , contraction (grammar) , lymph , anatomy , nitric oxide , chemistry , medicine , pathology
Nitric oxide produced by lymphatic endothelial cells is required for diastolic relaxation during lymphatic pumping. We propose increased lymph shear during contraction increases NO for relaxation. Additionally, valvular regions with endothelial‐coated valves might be a primary site for NO generation. Mesenteric lymph vessels of anesthetized rats were studied with NO microelectrodes during contractions. On both lymphatic bulb and downstream tubular regions, [NO] began to increase during each contraction and peaked after the contraction subsided. The valvular region [NO] was 1054+154 nM compared to 620+126 nM for tubular sites ∼ 500 um away (7 vessels, 4 rats). These [NO] are as high as that of nearby large arterioles. Outside the valvular wall by one adipocyte (∼40–60 um), the [NO] was 542+192 nanomolar, demonstrating the diffusion of NO away from the lymphatic to the surrounding tissue. As the frequency of contractions increased, the average [NO] increased and if spontaneous contractions declined, so did the average perilymphatic [NO]. The overall data indicate valvular areas of lymph vessels are capable of rapid NO responses to individual contractions and the average [NO] is contraction frequency dependent. Valvular regions may be the primary site of NO generation for the lymphatic vessels given the much higher [NO] than in downstream tubular regions. (Supported by HL70308)