Lung aryl hydrocarbon hydroxylase: inhibition following cadmium chloride inhalation. [Rats]

Journal Article · Thu Dec 01 04:00:00 EST 1983 · Environ. Res.; (United States)

DOI:https://doi.org/10.1016/0013-9351(83)90123-8· OSTI ID:6748127

Palmer, K C; Naseem, S M; Hayes, J A; Tishler, P V

Polycyclic hydrocarbon metabolism in male Spraque-Dawley rats following inhalation of aerosolized cadmium chloride (CdCl/sub 2/) was examined. Constitutive activity of microsomal aryl hydrocarbon hydroxylase (AHH) (benzo(a)pyrene substrate) was monitored in lung and liver homogenates up to 10 days after exposure. Lung AHH activity was reduced by 85% during the first 2 days following cadmium inhalation, and did not return to normal levels until 7 days after exposure. Enzyme activity in the livers of cadmium-treated animals was similarly depressed (by 65%) within 24 hr. Cadmium inhalation also inhibited (by 50%) 3-methylcholanthrene (MC) induction of lung AHH when compared with MC-treated controls. No significant effect on AHH inducibility by MC was noted in liver homogenates from cadmium-exposed animals. Nonspecific microsomal damage appeared not to occur since glucose-6-phosphatase activity in lung was unaffected by cadmium treatment. Although the mechanism of cadmium's action remains unclear, it appears not to involve a direct interaction of the metal with enzyme. The alteration of AHH activity by cadmium may result from injury to a specific cell type within the lung, which may be a major site of pulmonary AHH activity, or may result from modulation of synthesis and/or degradation of heme proteins in the lung. These results suggest that cadmium, under these conditions, markedly reduces the constitutive and inducible activity of AHH in the lung. 48 references.

• Research Organization: Wayne State Univ. School of Medicine, Detroit, MI
• OSTI ID: 6748127
• Journal Information: Environ. Res.; (United States), Journal Name: Environ. Res.; (United States) Vol. 32:2; ISSN ENVRA
• Country of Publication: United States
• Language: English

Related Subjects

3-METHYLCHOLANTHRENE
560305* -- Chemicals Metabolism & Toxicology-- Vertebrates-- (-1987)
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AEROSOLS
ANIMALS
AROMATICS
BIOASSAY
BIOLOGICAL EFFECTS
BODY
CADMIUM CHLORIDES
CADMIUM COMPOUNDS
CADMIUM HALIDES
CHLORIDES
CHLORINE COMPOUNDS
COLLOIDS
DIGESTIVE SYSTEM
DISPERSIONS
ENZYME ACTIVITY
ENZYMES
GLANDS
HALIDES
HALOGEN COMPOUNDS
HYDROCARBONS
HYDROXYLASES
INHALATION
INHIBITION
INTAKE
LIVER
LUNGS
MAMMALS
ORGANIC COMPOUNDS
ORGANS
OXIDOREDUCTASES
POLYCYCLIC AROMATIC HYDROCARBONS
RATS
RESPIRATORY SYSTEM
RODENTS
SOLS
VERTEBRATES