Sarac, BulentDurmus, NedimBagcivan, IhsanAltun, AhmetTuran, MustafaSencan, Mehmet2019-07-272019-07-282019-07-272019-07-2820100885-3177https://dx.doi.org/10.1097/MPA.0b013e3181d3645bhttps://hdl.handle.net/20.500.12418/9826Objectives: Nitric oxide (NO) is a potent nonadrenergic, noncholinergic mediator of gastrointestinal smooth muscle. We aimed to investigate the effects of new NO/cyclic guanosine monophosphate (cGMP) pathway-affecting agents at the sheep sphincter of Oddi (SO) in vitro. Methods: Sheep SO rings were mounted in organ baths and tested for isometric tension and cGMP levels in response to 3,3-bis(aminoethyl)-1-hydroxy-2-oxo-1-triazene; 3-morpholinosydnonimine hydrochloride (SIN-1); and BAY 41-2272 in the presence and absence of 1H-(1,2,4)oxadiazole(4,3-a)quinoxalin-1-one (ODQ). Results: 3,3-bis(Aminoethyl)-1-hydroxy-2-oxo-1-triazene; SIN-1; and BAY 41-2272 relaxed SO rings in a concentration-dependent manner. These relaxations were significantly decreased in the presence of ODQ (P < 0.05). All agents significantly increased the cGMP levels compared with the control group (P < 0.05). The increased cGMP levels in the 3,3-bis(aminoethyl)-1-hydroxy-2-oxo-1-triazene; and BAY 41-2272-treated groups were significantly different from both control and carbachol groups (P < 0.05), whereas the increase in the SIN-1 group was significantly different from all groups (P < 0.05). The cGMP levels were significantly lower in the presence of ODQ compared with its absence (P < 0.05). Conclusions: The relaxation of SO rings by these agents may be via increasing the levels of cGMP. The additional increase produced by SIN-1 may be the combined effects of NO generation and activation of guanylyl cyclase.en10.1097/MPA.0b013e3181d3645binfo:eu-repo/semantics/closedAccessSphincter of OddiNO/cGMP pathwaycGMPArticle396878875206972102-s2.0-77955180882Q2WOS:000280190900020Q2