title: Histopathological and histochemical studies of the skin of guinea pigs after long-term exposure to nitrogen dioxide.
abstract: Male guinea pigs were exposed to nitrogen dioxide (2 mg/m3) during 180 days (8 hours a day). Long-term exposure induced thickening of the corneal layer of the epidermis as well as inflammatory infiltrations in the proper skin. The following enzymes were estimated histochemically in skin samples of experimental and control animals: succinic dehydrogenase, NADH2-tetrazolium reductase, lactate dehydrogenase; alkaline phosphatase, acid phosphatase and adenosine triphosphatase. Chronic exposrue stimulated a decrease of NADH2-tetrazolium reductase in the epidermis and connective tissue components of proper skin and marked positive reaction of lactate dehydrogenase in epidermal cells and hair follicles. Increase of a diffuse reaction on adenosine triphosphatase in smooth muscles of the skin was found also in exposed animals.
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis; D000251:Adenosine Triphosphatases / Q000032:analysis; D000469:Alkaline Phosphatase / Q000032:analysis; D000818:Animals; D006168:Guinea Pigs; D006651:Histocytochemistry; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D008297:Male; D009246:NADH Tetrazolium Reductase / Q000032:analysis; D009585:Nitrogen Dioxide / Q000506:poisoning*; D012867:Skin / Q000201:enzymology* / Q000473:pathology; D013385:Succinate Dehydrogenase / Q000032:analysis
chemical_list: D007770:L-Lactate Dehydrogenase; D013385:Succinate Dehydrogenase; D009246:NADH Tetrazolium Reductase; D000469:Alkaline Phosphatase; D000135:Acid Phosphatase; D000251:Adenosine Triphosphatases; D009585:Nitrogen Dioxide