The 14CO2 breath test: facilities and limitations of a rapid and noninvasive method for in vivo evaluation of modified hepatic cytochrome P-450 ? a critique

1987 ◽  
Vol 60 (1-3) ◽  
pp. 81-85 ◽  
Author(s):  
M. Br�ch ◽  
L. Kling ◽  
W. Legrum ◽  
E. Maser
Keyword(s):  
Breath Test ◽  
Noninvasive Method ◽  
In Vivo Evaluation ◽  
14Co2 Breath Test ◽  
Cytochrome P 450 ◽  
Hepatic Cytochrome

In Vivo Interactions of Aluminum with Hepatic Cytochrome P-450 and Metallothionein

1987 ◽  
Vol 8 (4) ◽  
pp. 541-548
Author(s):  
E. H. JEFFERY ◽  
H. T. JANSEN ◽  
J. A. DELLINGER
Keyword(s):  
Cytochrome P 450 ◽  
Hepatic Cytochrome

scholarly journals Olfactory cytochrome P-450. Studies with suicide substrates of the haemoprotein

1988 ◽  
Vol 253 (2) ◽  
pp. 569-576 ◽  
Author(s):  
C J Reed ◽  
E A Lock ◽  
F De Matteis
Keyword(s):  
Olfactory Epithelium ◽  
Peroxidase Activity ◽  
Time Course ◽  
Cumene Hydroperoxide ◽  
Enzymic Activity ◽  
Cytochrome P 450 ◽  
Hepatic Cytochrome ◽  
Suicide Substrates

1. The olfactory epithelium of male hamsters has been found to be extremely active in the cumene hydroperoxide-supported oxidation of tetramethylphenylenediamine, and this peroxidase activity has been shown to be cytochrome P-450-dependent. 2. The interaction of a series of suicide substrates of cytochrome P-450 with the hepatic and olfactory mono-oxygenase systems has been assessed by determination of peroxidase, 7-ethoxycoumarin O-de-ethylase (ECOD) and 7-ethoxyresorufin O-de-ethylase (EROD) activities after treatment in vivo with these compounds. Chloramphenicol, OOS-trimethylphosphorothiolate and two dihydropyridines [DDC (3,5-diethoxycarbonyl-1,4-dihydrocollidine) and 4-ethyl DDC (3,5-diethoxycarbonyl-4-ethyl-1,4-dihydro-2,6-dimethylpyridine)] all caused similar percentage inhibitions of hepatic and olfactory activities, but the absolute amounts of enzymic activity lost were considerably greater in the latter tissue. In contrast, halothane had little effect upon hepatic cytochrome P-450-dependent reactions, whereas it severely inhibited those of the olfactory epithelium. 3. The time course of loss and recovery of hepatic and olfactory peroxidase, ECOD and EROD activities after a single dose of 4-ethyl DDC was studied. The rates of loss of activity observed were very similar, irrespective of tissue or reaction examined. In the olfactory epithelium, all three activities recovered concurrently and at a rate similar to that of the hepatic peroxidase activity. In contrast, the hepatic de-ethylation of 7-ethoxycoumarin and 7-ethoxy-resorufin recovered significantly more rapidly. 4. It is suggested that this behaviour is due to 4-ethyl DDC acting not only as a suicidal inhibitor but also as an inducer of certain forms of cytochrome P-450 in the liver; in the olfactory epithelium, however, inactivation, but not induction, occurs. Classical inducing agents were reported to have no effect upon olfactory cytochrome P-450, and in the present study neither phenobarbitone nor beta-naphthoflavone treatment had any effect upon olfactory cytochrome P-450-dependent reactions, although it induced those of the liver.

EXOGENOUS HEME FUNCTIONALLY RECONSTITUTES HEPATIC CYTOCHROME P-450 IN VIVO

1980 ◽  
pp. 587-590 ◽  
Author(s):  
Geoffrey C. Farrell ◽  
M. Almira Correia ◽  
Rudi Schmid ◽  
Paul R. Ortiz de Montellano ◽  
Kent L. Kunze
Keyword(s):  
Cytochrome P 450 ◽  
Hepatic Cytochrome

In Vitro and In Vivo Evaluation of the Effect of Puerarin on Hepatic Cytochrome P450-Mediated Drug Metabolism

Planta Medica ◽  
2014 ◽  
Vol 80 (07) ◽  
pp. 561-567 ◽  
Author(s):  
Sang-Bum Kim ◽  
In-Soo Yoon ◽  
Kyu-Sang Kim ◽  
Sung-Jun Cho ◽  
Yeong Kim ◽  
...  
Keyword(s):  
Cytochrome P450 ◽  
Drug Metabolism ◽  
In Vivo Evaluation ◽  
Hepatic Cytochrome

The use of saturation doses in the 14CO2 breath test allows measurement of the mixed function oxidase capacity in vivo

1985 ◽  
Vol 34 (3) ◽  
pp. 461-462 ◽  
Author(s):  
C. Steffen ◽  
Jutta Friebertshäuser ◽  
K.J. Netter
Keyword(s):  
Breath Test ◽  
Mixed Function Oxidase ◽  
14Co2 Breath Test

Exogenous heme restores in vivo functional capacity of hepatic cytochrome P-450 destroyed by allylisopropylacetamide

1979 ◽  
Vol 89 (2) ◽  
pp. 456-463 ◽  
Author(s):  
Geoffrey C. Farrell ◽  
Rudi Schmid ◽  
Kent L. Kunze ◽  
Paul R. Ortiz de Montellano
Keyword(s):  
Functional Capacity ◽  
Cytochrome P 450 ◽  
Hepatic Cytochrome
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