Effect of cadmium, mercury, and zinc on the hepatic microsomal enzymes of Channa punctatus

Journal Article · Wed Jun 01 00:00:00 EDT 1994 · Bulletin of Environmental Contamination and Toxicology; (United States)

DOI:https://doi.org/10.1007/BF00200699· OSTI ID:7026639

Dalal, R; Bhattacharya, S ^[1]

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1. School of Life Sciences, Santiniketan (India)

The increased use of heavy metals like cadmium and mercury in industry and agriculture, and their subsequent intrusion in indeterminate amounts into the environment has caused ecological and biological changes. In vivid contrast, zinc, one of the essential elements, and used in the cosmetic industry, is known to play a pivotal roles in various cellular processes. The seriousness and longevity of these metals in the environment are compounded by the fact that they are non-degradable with significant oxidizing capacity and substantial affinity for electronegative nucleophilic species in proteins and enzymes. Exposure of aquatic animals, especially fish, to these toxic metals for a prolonged period produces an intrinsic toxicity in relation to susceptible organs and/or tissues, although no serious morphological or anatomical changes in the animal or even their feeding behavior may occur. The p-hydroxylation of aniline by aniline hydroxylase (AH) and the N-demethylation of amines to generate formaldehyde (HCHO) by aminopyrine demethylase (APD) are the two oxygen-dependent reactions of microsomal mixed-function oxidase (MFOs) which control the pharmacological and toxicological activities of xenobiotics in mammalian and other species. While both these classical enzymes in fish are reported to demonstrate relatively low specific activity, they are used as criteria for delineating polluted areas. Unlike mammalian species, however, intoxication and interference of MFO enzymes by metal toxicants, especially during prolonged exposure, has not been investigated. The present report describes the results of studies from the concurrent exposure for 28 d to cadmium (CdCl[sub 2]), mercury (HgCl[sub 2]) or zinc (ZnCl[sub 2]) individually, on the AH and APD activities and microsomal protein content in liver of freshwater teleost Channa punctatus.

• OSTI ID: 7026639
• Journal Information: Bulletin of Environmental Contamination and Toxicology; (United States), Vol. 52:6; ISSN 0007-4861
• Country of Publication: United States
• Language: English

Related Subjects

63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
CADMIUM
BIOLOGICAL EFFECTS
FISHES
LIVER
BIOCHEMISTRY
MERCURY
ZINC
ENZYMES
TOXICITY
ANIMALS
AQUATIC ORGANISMS
BODY
CHEMISTRY
DIGESTIVE SYSTEM
ELEMENTS
GLANDS
METALS
ORGANIC COMPOUNDS
ORGANS
PROTEINS
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology