title: Effect of Aurantii Fructus Immaturus Flavonoid on the Contraction of Isolated Gastric Smooth Muscle Strips in Rats.
abstract: This study was designed to investigate the effect of Aurantii fructus immaturus flavonoid (AFIF) on the contraction of isolated gastric smooth muscle in rats and explore its underlying mechanisms. Isolated antral longitudinal smooth muscle strip (ALSMS) and pyloric circular smooth muscle strip (PCSMS) of rats were suspended in tissue chambers. The responses of ALSMS and PCSMS to administration of AFIF were observed. Cyclic guanosine monophosphate (cGMP) and protein kinase G (PKG) levels of PCSMS were measured by ELISA kits. In this study, AFIF showed no significant effect on ALSMS contraction, but it dose-dependently reduced the mean contraction amplitude of PCSMS. When the concentration of AFIF reached 3000 μg/mL, 6000 μg/mL, and 10000 μg/mL, its inhibitory effect on PCSMS contraction was significant. This effect of AFIF was weakened in Ca(2+)-rich environment. And Nω-nitro-L-arginine methyl (L-NAME), the inhibitor of nitric oxide synthase (NOS), significantly inhibited AFIF's action in comparison with control (P < 0.05). After incubation with AFIF for 30 min, levels of cGMP and PKG in PCSMS were significantly increased compared with control (P < 0.05). Our results suggest that AFIF has a dose-dependent diastolic effect on PCSMS in rats, which may be related to the regulatory pathway of NO/cGMP/PKG/Ca(2+).
authors.affiliation: Digestive Disease Center, Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, Beijing 100010, China.
authors.forename: Zhenyu
authors.identifier: 0000-0002-8911-7031
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Digestive Disease Center, Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, Beijing 100010, China.
authors.forename: Shengsheng
authors.identifier: 0000-0003-0457-1727
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Digestive Disease Center, Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, Beijing 100010, China.
authors.forename: Peicai
authors.initials: P
authors.lastname: Li
authors.affiliation: Digestive Disease Center, Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, Beijing 100010, China.
authors.forename: Xiaofang
authors.identifier: 0000-0002-1837-1091
authors.initials: X
authors.lastname: Lu
authors.affiliation: Digestive Disease Center, Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, Beijing 100010, China.
authors.forename: Jiajia
authors.identifier: 0000-0002-6581-1774
authors.initials: J
authors.lastname: Wang
authors.affiliation: Digestive Disease Center, Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, Beijing 100010, China.
authors.forename: Luqing
authors.identifier: 0000-0003-1986-3511
authors.initials: L
authors.lastname: Zhao
authors.affiliation: Digestive Disease Center, Beijing Hospital of Traditional Chinese Medicine Affiliated to Capital Medical University, Beijing 100010, China.
authors.forename: Yueqi
authors.initials: Y
authors.lastname: Wang