title: Effects of LPS, PLA(2) and OFR on proton translocation across inner mitochondrial membrane and H(+)-ATPase in the liver.
abstract: OBJECTIVE: To elucidate the effects of lipopolysaccharide (LPS), phospholipase A(2) (PLA(2)) and oxygen free radical (OFR) on proton transmembrane translocation and H(+)-ATPase. METHODS: The normal rats were sacrificed for preparetion liver mitochondria and submitochondrial particles for experiments in vitro. Submitochondrial particles were incubated with LPS (100 &mgr;g/mL), PLA(2) (10 u/mL) and FeSO(4)/Vit C (30/90 &mgr;mol/L) at 30 degrees C for 30 min. The proton translocation of submitochondrial particles (SMPs) were assayed with the fluorescent probe ACMA (9-amino-6-chloro-2 methoxya cridine). The mitochondria were incubated with different concentration of LPS, PLA(2) and FeSO(4)/Vit C. The H(+)-ATPase, PLA(2) and malondialdehyde (MDA) were assayed. RESULTS: The fluorescent quenching of ACMA and H(+)-ATPase activity in high dose was significantly decreased after treatment with LPS, PLA(2), FeSO(4)/Vit C (P<0.05). The mitochondrial PLA(2) activity and MDA content were significantly increased after treatment with LPS (P<0.01). CONCLUSIONS: FeSO(4)/Vit C in low dose causes increases H(+)-ATPase activity. LPS, PLA(2), FeSO(4)/Vit C might be the important factors changing H(+)-ATPase and proton translocation across the membrane.
authors.affiliation: Research Institute of Surgery, Daping, Chongqing 400042, China.
authors.forename: Songmin
authors.initials: S
authors.lastname: Lu
authors.forename: Heming
authors.initials: H
authors.lastname: Yang
authors.forename: Shuangming
authors.initials: S
authors.lastname: Song
authors.forename: Jiancang
authors.initials: J
authors.lastname: Liu
authors.forename: Ping
authors.initials: P
authors.lastname: Li
authors.forename: Zhihong
authors.initials: Z
authors.lastname: Wan
authors.forename: Houjun
authors.initials: H
authors.lastname: Jia