Biomaterial Database

Genotoxicity studies on mice after short term inhalation exposure to methyl isocyanate. 1989

R N Kar, and K A Khan, and N Sethi

Division of Toxicology, Central Drug Research Institute, Lucknow, India.

Mutagenicity testing is an important aspect of the toxicological evaluation of environmental chemicals for safety. Methyl isocyanate (MIC), a very hazardous chemical used for the manufacture of insecticides, was studied for its genotoxic effects on the somatic cells of mice after inhalation exposure by means of an in vivo micronucleus test and chromosomal analysis of bone marrow cells. Animals were exposed for 10 min to different concentrations (2.40, 4.80 or 7.20 microliters) of MIC in a 22 litre chamber at 0 and 24 h. Bone marrow smears prepared 6 h after the second treatment were examined for the occurrence of micronuclei (MN) in polychromatic (P) and normochromatic (N) erythrocytes. The frequencies of cells with MN and the P/N ratio did not differ significantly from those of the control at all the exposure levels. Chromosomal preparations revealed few structural and numerical abnormalities. Aberrations encountered were of the chromatid type only. Quantitative analyses failed to exhibit any significant increase in aberration rates in the three treated groups. Numerical abnormalities were within the control range.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009153	Mutagens	Chemical agents that increase the rate of genetic mutation by interfering with the function of nucleic acids. A clastogen is a specific mutagen that causes breaks in chromosomes.	Clastogen,Clastogens,Genotoxin,Genotoxins,Mutagen
D001853	Bone Marrow	The soft tissue filling the cavities of bones. Bone marrow exists in two types, yellow and red. Yellow marrow is found in the large cavities of large bones and consists mostly of fat cells and a few primitive blood cells. Red marrow is a hematopoietic tissue and is the site of production of erythrocytes and granular leukocytes. Bone marrow is made up of a framework of connective tissue containing branching fibers with the frame being filled with marrow cells.	Marrow,Red Marrow,Yellow Marrow,Marrow, Bone,Marrow, Red,Marrow, Yellow
D002869	Chromosome Aberrations	Abnormal number or structure of chromosomes. Chromosome aberrations may result in CHROMOSOME DISORDERS.	Autosome Abnormalities,Cytogenetic Aberrations,Abnormalities, Autosome,Abnormalities, Chromosomal,Abnormalities, Chromosome,Chromosomal Aberrations,Chromosome Abnormalities,Cytogenetic Abnormalities,Aberration, Chromosomal,Aberration, Chromosome,Aberration, Cytogenetic,Aberrations, Chromosomal,Aberrations, Chromosome,Aberrations, Cytogenetic,Abnormalities, Cytogenetic,Abnormality, Autosome,Abnormality, Chromosomal,Abnormality, Chromosome,Abnormality, Cytogenetic,Autosome Abnormality,Chromosomal Aberration,Chromosomal Abnormalities,Chromosomal Abnormality,Chromosome Aberration,Chromosome Abnormality,Cytogenetic Aberration,Cytogenetic Abnormality
D003485	Cyanates	Organic salts of cyanic acid containing the -OCN radical.	Cyanate
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D005260	Female		Females
D000280	Administration, Inhalation	The administration of drugs by the respiratory route. It includes insufflation into the respiratory tract.	Drug Administration, Inhalation,Drug Administration, Respiratory,Drug Aerosol Therapy,Inhalation Drug Administration,Inhalation of Drugs,Respiratory Drug Administration,Aerosol Drug Therapy,Aerosol Therapy, Drug,Drug Therapy, Aerosol,Inhalation Administration,Administration, Inhalation Drug,Administration, Respiratory Drug,Therapy, Aerosol Drug,Therapy, Drug Aerosol
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D015162	Micronucleus Tests	Induction and quantitative measurement of chromosomal damage leading to the formation of micronuclei (MICRONUCLEI, CHROMOSOME-DEFECTIVE) in cells which have been exposed to genotoxic agents or IONIZING RADIATION.	Micronucleus Assays,Assay, Micronucleus,Assays, Micronucleus,Micronucleus Assay,Micronucleus Test,Test, Micronucleus,Tests, Micronucleus