The ability of the murine erythron to respond to hemolytic doses of phenylhydrazine is significantly impaired by exposures to 10 ppm benzene.
Male C57Bl mice were given 50 exposures (6 h/d x 5 d/wk x 10 wk) to 10 ppm benzene. At regular intervals during the course of the exposures, the numbers of erythroid colony-forming cells (CFU-E) and the numbers of granulocytic colony-forming cells (GM-CFU-C) were assayed. At the end of the benzene exposures, additional groups of mice were given 4 daily injections of phenylhydrazine (PHZ) to induce anemia. During the course of the exposures, the numbers of colony-forming cells from benzene-exposed mice were, with infrequent exceptions, statistically indistinguishable from the numbers of these cells in air-exposed mice. However, in response to the PHZ-induced anemia, the numbers of late erythroid (CFU-E) and granulocytic (GM-CFU-C) progenitor cells were about 30% lower among benzene-exposed mice than among air-exposed mice. These results suggest that concentrations of benzene that induce little or no observable hematopoietic changes may, in fact, greatly alter the hematopoietic capacity of an exposed individual.
Dempster
A M
AM
Institute of Environmental Medicine, New York University Medical Center, NY 10016.
Snyder
C A
CA
D000743:Anemia, Hemolytic / Q000139:chemically induced; D000818:Animals; D001554:Benzene / Q000633:toxicity*; D004912:Erythrocytes / Q000187:drug effects*; D006412:Hematopoietic Stem Cells / Q000187:drug effects*; D006461:Hemolysis / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010659:Phenylhydrazines / Q000633:toxicity*
D010659:Phenylhydrazines; C030299:phenylhydrazine; D001554:Benzene