Kinetic Analysis of Enzymatic Reaction of Active Components from Xinshao Formula in Liver Microsomes of Sham-Operated and Cerebral Ischemia-reperfusion Injury Rats / 中国实验方剂学杂志

ABSTRACT

Objective: To investigate and compare enzymatic kinetics of scutellarin,apigenin-7-O-glucronide and paeoniflorin from Xinshao fomula in liver microsomes of sham-operated rats and middle cerebral artery occlusion(MCAO) rats with focal cerebral ischemia-reperfusion injury. Method: Xinshao fomula were incubated respectively with liver microsomes of sham-operated rats and MCAO rats,UPLC-MS and substrate elimination method was employed,Michaelis constant(Km),maximum velocity of enzymatic reaction(Vmax) and intrinsic clearance(CLint) of these three components from Xinshao fomula in liver microsomes of sham-operated rats and MCAO rats were calculated,these parameters between different groups were evaluated by statistical analysis. Result: The Km values of scutellarin,apigenin-7-O-glucronide and paeoniflorin in liver microsomes of MCAO rats were (0.798±0.031),(0.213±0.017),(0.499±0.029) μmol·L-1,which were quite different to these in liver microsomes of sham-operated rats.Compared with the sham-operated group,Vmax and CLint values of scutellarin and paeoniflorin in liver microsomes of MCAO rats were significantly reduced(PPVmax of apigenin-7-O-glucronide in liver microsomes of MCAO rat was also significantly reduced(PConclusion: Metabolic rates of these three active components from Xinshao fomula in liver microsomes of MCAO rats with focal cerebral ischemia-reperfusion injury decrease with low elimination rate.