title: Effect of cyclic AMP on barrier function of human lymphatic microvascular tubes.
abstract: This work examines the effect of cyclic AMP (cAMP) on the in vitro barrier function of tubes of human dermal lymphatic microvascular endothelial cells (LECs). Under baseline conditions, the barrier function of LEC tubes was weak, with diffusional permeability coefficients to bovine serum albumin and 10 kDa dextran of 1.4(-0.6)(+0.9)x10(-6) cm/s and 1.7(-0.5)(+0.8)x10(-6) cm/s (geometric mean+/-95% CI), respectively, and 1.2+/-0.5 (mean+/-95% CI) focal leaks per mm. Exposure to low concentrations (3 microM) of a cell-permeant analog of cAMP did not alter the barrier function. Exposure to higher concentrations (80 and 400 microM) and/or the phosphodiesterase inhibitor Ro-20-1724 (20 microM) lowered permeabilities and the number of focal leaks, and increased the selectivity of the barrier. Decreased permeabilities were accompanied by an increase in continuous VE-cadherin staining at cell-cell borders. Exposure to 1 mM 2',5'-dideoxyadenosine, an inhibitor of adenylate cyclase, did not increase permeabilities. LECs expressed the lymphatic-specific master transcription factor Prox-1, regardless of whether barrier function was weak or strong. Our results indicate that the permeability of LEC tubes in vitro responds to cAMP in a manner similar to that well-described for the permeability of blood microvessels.
authors.affiliation: Department of Biomedical Engineering, Boston University, 44 Cummington Street, Boston, MA 02215, USA.
authors.forename: Gavrielle M
authors.initials: GM
authors.lastname: Price
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Chrobak
authors.forename: Joe
authors.initials: J
authors.lastname: Tien
mesh_terms: D012368:4-(3-Butoxy-4-methoxybenzyl)-2-imidazolidinone / Q000494:pharmacology; D000067956:Adenylyl Cyclase Inhibitors; D022005:Adherens Junctions / Q000187:drug effects / Q000378:metabolism; D015703:Antigens, CD / Q000378:metabolism; D003994:Bucladesine / Q000494:pharmacology; D015820:Cadherins / Q000378:metabolism; D002199:Capillary Permeability / Q000187:drug effects*; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000031:analogs & derivatives / Q000494:pharmacology*; D003911:Dextrans / Q000378:metabolism; D016048:Dideoxyadenosine / Q000031:analogs & derivatives / Q000494:pharmacology; D042783:Endothelial Cells / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D004729:Endothelium, Lymphatic / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D004791:Enzyme Inhibitors / Q000494:pharmacology; D018398:Homeodomain Proteins / Q000378:metabolism; D006801:Humans; D008562:Membrane Glycoproteins / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism; D019408:Platelet Endothelial Cell Adhesion Molecule-1 / Q000378:metabolism; D012710:Serum Albumin, Bovine / Q000378:metabolism; D019108:Tight Junctions / Q000187:drug effects / Q000378:metabolism; D023822:Tissue Engineering / Q000379:methods; D025521:Tumor Suppressor Proteins / Q000378:metabolism; D062826:Zonula Occludens-1 Protein; D000098551:Prospero-Related Homeobox 1 Protein; D000099152:Cadherin 5; D000098853:Podoplanin
chemical_list: D012368:4-(3-Butoxy-4-methoxybenzyl)-2-imidazolidinone; D000067956:Adenylyl Cyclase Inhibitors; D015703:Antigens, CD; D003994:Bucladesine; D015820:Cadherins; D000242:Cyclic AMP; D003911:Dextrans; D016048:Dideoxyadenosine; D004791:Enzyme Inhibitors; D018398:Homeodomain Proteins; D008562:Membrane Glycoproteins; D008565:Membrane Proteins; D010750:Phosphoproteins; D019408:Platelet Endothelial Cell Adhesion Molecule-1; D012710:Serum Albumin, Bovine; D025521:Tumor Suppressor Proteins; D062826:Zonula Occludens-1 Protein; D000098551:Prospero-Related Homeobox 1 Protein; D000099152:Cadherin 5; C117468:PDPN protein, human; D000098853:Podoplanin; C569042:TJP1 protein, human; C021008:2',5'-dideoxyadenosine