Caffeine is a marker drug for testing the activity of CYP1A2 (3-N-demethylation) in humans and rats. Moreover, it is also a relatively specific substrate of CYP3A (8-hydroxylation). In the case of 1-N- and in particular 7-N-demethylation of caffeine, apart from CYP1A2, other cytochrome P-450 isoenzymes play a considerable role. The aim of the present study was to investigate the influence of im...

Nithipatikom, Kasem, Michael P. Endsley, Jeannine M. Moore, Marilyn A. Isbell, John R. Falck, William B. Campbell, and Garrett J. Gross. Effects of selective inhibition of cytochrome P-450 -hydroxylases and ischemic preconditioning in myocardial protection. Am J Physiol Heart Circ Physiol 290: H500–H505, 2006. First published October 7, 2005; doi:10.1152/ajpheart.00918.2005.—Cytochrome P-450 (C...

background increasing evidence indicates that opiate users and methadone maintenance patients (mmps) are impaired in executive control tasks and response inhibition behavior compared to healthy individuals; however, the cognitive functional difference between opiate addicts and mmps has not been clarified. objectives this study employed go/no-go tasks to evaluate the response inhibition behavio...

onion (allium cepa) contains high levels of flavonoids. although there are many studies indicating the inhibitory effects of flavonoids on xanthine oxidase, there is no report on the effect of onion on this enzyme. therefore, in the present study, the inhibitory effects of onion on xanthine oxidase are investigated. fresh filtered juice of onion was prepared and its inhibitory effect on guinea ...

glutathione s-transferases (gsts) are widespread in fasciola. hepatica parasite and sheep liver tissue. study of gsts inhibition assays in f. hepatica and sheep liver tissue are a priority of chemotherapeutic targets in parasitic liver diseases including human fascioliasis in iran. in this research, the whole extract of f. hepatica and sheep liver tissues were purified and eluted for sodium dod...

We expressed mouse cytochrome P1-450 and P3-450 using recombinant vaccinia virus gene expression system in HeLa cells that were devoid of significant basal levels of P-450. HeLa cells were infected with the recombinant vaccinia virus containing either mouse cytochrome P1-450 or P3-450 cDNA, and the cell lysates were analyzed for the kinetics of P-450 enzyme activity and protein expression at th...

A defining feature of glial cells has been their inability to generate action potentials. We show here that there are two distinct types of morphologically identical oligodendrocyte precursor glial cells (OPCs) in situ in rat CNS white matter. One type expresses voltage-gated sodium and potassium channels, generates action potentials when depolarized and senses its environment by receiving exci...

Phospholipid has been reported to be necessary for optimal catalytic activity of a number of mammalian cytochrome P-450 (P-450) systems. We also confirm that a number of individual phospholipids and mixtures, used as soluble monomers or phospholipid vesicles, show activation of 7-ethoxycoumarin O-deethylase activity by an enzyme system composed of rat liver microsomal P-450PB-B and NADPH-P-450 ...

The binding of thiol, thiolate, thioether, and disulfide sulfur donor ligands to ferric cytochrome P-450-CAM and myoglobin has been investigated by W-visible absorption, magnetic circular dichroism (MCD), and EPR spectroscopy. For ferric P-450, the binding of all sulfur donors is competitive with substrate binding. Addition of thiols to P-450 leads to interconvertible thiol or thiolate-bound sp...