Nitric oxide modulates endotoxin-induced platelet-endothelial cell adhesion in intestinal venules.
Although platelets have been implicated in the pathogenesis of vascular diseases, little is known about factors that regulate interactions between platelets and the vessel wall under physiological conditions. The objectives of this study were to 1) define the contribution of nitric oxide (NO) to endotoxin (lipopolysaccharide, LPS)-induced platelet-endothelial cell (P/E) adhesion in murine intestinal venules and 2) determine whether the antiadhesive action of NO is mediated by soluble guanylate cyclase (sGC). Adhesive interactions between platelets and endothelial cells were monitored by intravital microscopy. LPS administration into control wild-type mice (WT) resulted in a >15-fold increase in P/E adhesion. Similar responses were observed using endothelial NO synthase (eNOS)-deficient platelets. However, treatment with the NO donor diethylenetriamine-nitric oxide (DETA-NO) attenuated the P/E adhesion response to LPS, whereas the NO synthase inhibitor N(G)-nitro-L-arginine methyl ester or eNOS deficiency resulted in an exacerbation. P/E adhesion response did not differ between LPS-treated WT and inducible NOS-deficient mice. Inhibition of sGC abolished the attenuating effects of DETA-NO, whereas the sGC activator 3-(5'-hydroxymethyl-2'-furyl)-1-benzyl indazole (YC-1) reduced LPS-induced P/E adhesion. These findings indicate that 1) eNOS-derived NO attenuates endotoxin-induced P/E adhesion and 2) sGC is responsible for the antiadhesive action of NO.
Cerwinka
Wolfgang H
WH
Department of Molecular and Cellular Physiology, Louisiana State University Health Sciences Center, Shreveport, Louisiana 71130-3932, USA.
Cooper
Dianne
D
Krieglstein
Christian F
CF
Feelisch
Martin
M
Granger
D Neil
DN
D000818:Animals; D004730:Endothelium, Vascular / Q000187:drug effects / Q000502:physiology*; D004731:Endotoxins / Q000494:pharmacology*; D004926:Escherichia coli; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008856:Microscopy, Fluorescence; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000172:deficiency / Q000235:genetics / Q000378:metabolism; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D010973:Platelet Adhesiveness / Q000187:drug effects*; D014699:Venules / Q000187:drug effects / Q000502:physiology*
D004731:Endotoxins; D008070:Lipopolysaccharides; D009569:Nitric Oxide; D019001:Nitric Oxide Synthase; D052248:Nitric Oxide Synthase Type I; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496321:Nos1 protein, mouse; C496317:Nos2 protein, mouse; C496315:Nos3 protein, mouse