1.The Fourth Affiliated Hospital of Zhengjiang University School of Medicine, Yiwu 322000, China; 2.The Clinical Pharmacy �� Pharmacology Institute,The Xiangya Second Hospital, Central South University, Changsha 410011, China
Abstract��
OBJECTIVE To evaluate the affinity of brucine, a central stimulant, with P-gp in vitro, and predict its potential as a P-gp substrate in vivo.METHODS ATPase assay was used to evaluate the affinity of brucine with P-gp. During the energy-dependent P-gp drug transport process, adenosine triphosphate (ATP) are hydrolyzed to adenosine diphosphate (ADP) by ATPase. In the meantime, inorganic phosphate is released and the concentration could be measured to evaluate the affinity of brucine with P-gp. Verapamil was included as a positive control. The properties of brucine across the in vitro BBB model were studied. RESULTS The ATPase assay suggested that the Vmax/Km value of brucine (1.6 ��103min-1) was comparable with that of verapamil (2.9��103 min-1). The RESULTS of transport experiment showed that in the absence of P-glycoprotein inhibitor verapamile, the degree of the brucine transport from basal-to-apical was higher than the one from apical-to-basal at three concentrations (P��0.05), and the ER were 1.32, 1.56 and 1.54,respectively. However, when verapamile was added, the ER of three concentrations were decreased (P��0.05). CONCLUSION Brucine showed P-gp substrate characteristics of moderate intensity, although its affinity was not as high as verapamil. The result suggests that P-gp is likely to influence the access of brucine into the brain to some degree. In vivo studies are needed to confirm this finding.
XU Dan-Hua-,
,
LOU Ting- etc
.Evaluation of in Vitro Affinity of Brucine to P-glycoprotein[J] Chinese Pharmaceutical Journal, 2014,V49(18): 1631-1636
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2014, Vol. 49 
