Enhanced aryl hydrocarbon hydroxylase activity after interaction between solubilized cytochrome P-448 and microsomes low in endogenous cytochrome P-450

1980 ◽  
Vol 29 (9) ◽  
pp. 1261-1270 ◽  
Author(s):  
Kirk T. Kitchin
Keyword(s):  
Aryl Hydrocarbon Hydroxylase ◽  
Hydroxylase Activity ◽  
Aryl Hydrocarbon ◽  
Aryl Hydrocarbon Hydroxylase Activity ◽  
Cytochrome P 450

scholarly journals On the occurrence of cytochrome P-450 and aryl hydrocarbon hydroxylase activity in rat brain.

1977 ◽  
Vol 145 (6) ◽  
pp. 1607-1611 ◽  
Author(s):  
J A Cohn ◽  
A P Alvares ◽  
A Kappas
Keyword(s):  
Carbon Monoxide ◽  
Rat Brain ◽  
Specific Activity ◽  
Aryl Hydrocarbon Hydroxylase ◽  
Hydroxylase Activity ◽  
Difference Spectra ◽  
Aryl Hydrocarbon ◽  
Brain Microsomes ◽  
Aryl Hydrocarbon Hydroxylase Activity ◽  
Cytochrome P 450

The difference spectra of the carbon monoxide-complex of dithionite-reduced rat brain microsomes, compared with both reduced microsomes, alone, and the carbon monoxide-complex of oxidized microsomes, indicate the presence of small amounts of cytochrome P-450 in brain. As in liver, cytochrome P-450 in brain is degraded in vitro to its inactive form, cytochrome P-420 by methylmercury chloride. Aryl hydrocarbon hydroxylase activity is also present in rat brain microsomes and, at lower specific activity, in brain homogenates. This carcinogen metabolizing activity is increased four-fold in rats pretreated with 3-methylcholanthrene.

Pulmonary toxicity of 1,1-dichloroethylene: correlation of early changes with covalent binding

1986 ◽  
Vol 64 (2) ◽  
pp. 112-121 ◽  
Author(s):  
P. G. Forkert ◽  
V. Stringer ◽  
K. M. Troughton
Keyword(s):  
Structural Damage ◽  
Covalent Binding ◽  
Significant Inhibition ◽  
Clara Cells ◽  
Aryl Hydrocarbon Hydroxylase ◽  
Hydroxylase Activity ◽  
Aryl Hydrocarbon ◽  
Temporal Correlations ◽  
Aryl Hydrocarbon Hydroxylase Activity ◽  
Cytochrome P 450

Administration of a single intraperitoneal dose of 1,1-dichloroethylene (125 mg/kg,1,1-DCE) to mice resulted in bronchiolar injury with selective necrosis of Clara cells. Degenerative changes were manifest in Clara cells as early as 1 h following 1,1-DCE exposure, and were characterized by marked swelling of mitochondria and aggregation of chromatin against the nuclear membrane. Cell death was apparent at 2 h; by 8 h, areas of the bronchiolar epithelium were devoid of lining cells, and at 24 h, the majority of Clara cells were exfoliated. The residual epithelium consisted of flattened cells which formed a thin lining for the airway. Necrosis of Clara cells early in the course of 1,1-DCE exposure coincided with peak covalent binding of [14C] 1,1-DCE and significant depression of components of the pulmonary mixed-function oxidase system; cytochrome P-450 and aryl hydrocarbon hydroxylase activity were markedly reduced but not depleted. Liver damage involving centrilobular hepatocytes was observed at 24 h in 30% of treated animals, and coincided with significant inhibition of aryl hydrocarbon hydroxylase activity; cytochrome P-450 content, however, remained unchanged. While changes in the liver evoked by 1,1-DCE were less striking, the results in lung demonstrate positive temporal correlations between structural damage, peak covalent binding and disturbances of monooxygenase enzymes.

Aryl Hydrocarbon Hydroxylase Activity “Of Mice and Humans”

1983 ◽  
pp. 179-197 ◽  
Author(s):  
R. E. Kouri ◽  
R. A. Lubet ◽  
C. E. McKinney ◽  
G. M. Connolly ◽  
D. W. Nebert ◽  
...  
Keyword(s):  
Aryl Hydrocarbon Hydroxylase ◽  
Hydroxylase Activity ◽  
Aryl Hydrocarbon ◽  
Aryl Hydrocarbon Hydroxylase Activity
Sign in / Sign up

Export Citation Format

Share Document