title: Nitric oxide-mediated vasorelaxation induced by sodium polyoxyethylene laurylether sulfate.
abstract: Ingestion of surfactants is known to cause hemodynamic changes with decreased total vascular resistance. Motivated by this clinical observation, we investigated the direct effects of a common anionic surfactant, sodium polyoxyethylene laurylether sulfate (LES), on isolated ring segments of rat thoracic aorta. LES did not produce any vasocontractile responses, but relaxed ring segments precontracted with 10(-6) M phenylephrine in a concentration-dependent manner. This LES-induced vasorelaxation was significantly reduced by the removal of endothelium or pretreatment with N(G)-nitro-L-arginine methylester hydrochloride, methylene blue, or oxyhemoglobin to the same degree, but was not affected by pretreatment with indomethacin. A further study measuring NO2- plus NO3- (NO(x), total metabolites of NO) in the medium of calf pulmonary artery endothelial (CPAE) cells, a cultured cell line, revealed that LES caused a significant increase in NO(x) production. On the other hand, in a study measuring intracellular Ca2+ in fura-2-loaded CPAE cells, LES caused a significant increase in intracellular Ca2+. These results suggest that LES causes endothelium-dependent vasorelaxation via a NO-mediated signaling pathway, which might be due to Ca2+ mobilization.
authors.affiliation: Department of Emergency Medicine, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan.
authors.forename: K
authors.initials: K
authors.lastname: Koyama
authors.forename: Y
authors.initials: Y
authors.lastname: Kasuya
authors.forename: K
authors.initials: K
authors.lastname: Koyama
authors.forename: K
authors.initials: K
authors.lastname: Goto
mesh_terms: D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D002118:Calcium / Q000378:metabolism; D002417:Cattle; D002460:Cell Line; D003470:Culture Media; D003902:Detergents / Q000494:pharmacology; D004730:Endothelium, Vascular / Q000187:drug effects; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009569:Nitric Oxide / Q000502:physiology*; D009924:Organ Culture Techniques; D000077423:Polidocanol; D011092:Polyethylene Glycols / Q000494:pharmacology*; D011651:Pulmonary Artery / Q000166:cytology / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D014664:Vasodilation / Q000187:drug effects*
chemical_list: D003470:Culture Media; D003902:Detergents; D000077423:Polidocanol; D009569:Nitric Oxide; D011092:Polyethylene Glycols; D002118:Calcium