title: Endothelium-dependent relaxation is depressed at the macro- and microcirculatory levels during sepsis.
abstract: The objective of this study was to determine whether endothelium-derived nitric oxide (NO) production is reduced at the macrocirculatory and microcirculatory levels during sepsis. To examine this, rats were subjected to sepsis by cecal ligation and puncture (CLP). At 5 h after CLP (i.e., midpoint of hyperdynamic sepsis) or sham operation, the aorta and superior mesenteric artery were isolated. Responses to an endothelium-dependent vasodilator, acetylcholine (ACh), and an endothelium-independent vasodilator, nitroglycerin (NTG), were determined. In additional studies, the small intestine was isolated 5 or 20 h (hypodynamic sepsis) after CLP. Responses to ACh and NTG were determined in the isolated intestine. The results indicate that endothelium-dependent relaxation in both the aorta and superior mesenteric artery was depressed at 5 h after CLP. In contrast, there was no significant difference in the relaxation induced by NTG. Moreover, ACh-induced vascular relaxation in the isolated small intestine decreased at 5 and 20 h post-CLP without any significant alterations in NTG-induced relaxation. Since studies have shown that ACh-induced relaxation in the aorta is reduced at 20 h after CLP, it could be concluded that endothelium-derived NO release is depressed during hyperdynamic and hypodynamic stages of sepsis, not only in large arteries, but also at the microcirculatory level.
authors.affiliation: Department of Surgery, Michigan State University, East Lansing 48824, USA.
authors.forename: P
authors.initials: P
authors.lastname: Wang
authors.forename: Z F
authors.initials: ZF
authors.lastname: Ba
authors.forename: I H
authors.initials: IH
authors.lastname: Chaudry
mesh_terms: D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000187:drug effects / Q000503:physiopathology; D001120:Arginine / Q000031:analogs & derivatives / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000502:physiology*; D066298:In Vitro Techniques; D007239:Infections / Q000503:physiopathology*; D007421:Intestine, Small / Q000098:blood supply; D008297:Male; D008638:Mesenteric Arteries / Q000187:drug effects / Q000503:physiopathology; D008833:Microcirculation; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D005996:Nitroglycerin / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D014655:Vascular Resistance; D014664:Vasodilation / Q000187:drug effects / Q000502:physiology*; D019323:omega-N-Methylarginine
chemical_list: D019323:omega-N-Methylarginine; D001120:Arginine; D019001:Nitric Oxide Synthase; D005996:Nitroglycerin; D000109:Acetylcholine