Inhalation toxicity of methyl isocyanate: biochemical and cytological profile of bronchoalveolar lavage fluid in rats.
Acute pulmonary injury in rats following a single inhalation exposure to methyl isocyanate (3.2 mg l-1) was reflected by alterations in the biochemical and cytological constituents of bronchoalveolar lavage fluid (BALF) over a period of 30 days. Total protein, sialic acid and lactic acid contents of BALF were increased followed by a gradual decline to normalcy between day 3 and day 30 post-exposure. The activity of lactic dehydrogenase also increased progressively with time. The cellularity of BALF was increased significantly and primarily comprised of polymorphonuclear neutrophils at 8 days. The adherence of macrophages was unchanged but their viability was lowered at 30 days post-exposure. The results indicate the significance of bronchoalveolar lavage analysis in monitoring pulmonary toxicity by methyl isocyanate, which is characterized by the hypoxic condition and reduced cellular defence. Some toxic manifestations are potentially reversible with time after cessation of exposure.
Inhalation Toxicology Section, Industrial Toxicology Research Centre, Lucknow, India.
G S
GS
Gupta
J L
JL
Kaw
S H
SH
Naqvi
R
R
Dixit
P K
PK
Ray
D000280:Administration, Inhalation; D000818:Animals; D000986:Antisickling Agents / Q000008:administration & dosage / Q000633:toxicity*; D001835:Body Weight / Q000187:drug effects; D001992:Bronchoalveolar Lavage Fluid / Q000737:chemistry* / Q000166:cytology / Q000209:etiology; D003485:Cyanates / Q000008:administration & dosage / Q000633:toxicity*; D017953:Isocyanates; D007773:Lactates / Q000378:metabolism; D019344:Lactic Acid; D008168:Lung / Q000187:drug effects; D008297:Male; D019158:N-Acetylneuraminic Acid; D011506:Proteins / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D012794:Sialic Acids / Q000378:metabolism; D014132:Trachea / Q000187:drug effects
D000986:Antisickling Agents; D003485:Cyanates; D017953:Isocyanates; D007773:Lactates; D011506:Proteins; D012794:Sialic Acids; D019344:Lactic Acid; C008461:methyl isocyanate; D019158:N-Acetylneuraminic Acid