Effects of diesel exhaust particles on the male reproductive system in strains of mice with different aryl hydrocarbon receptor responsiveness.
Diesel exhaust particles (DEPs) contain polycyclic aromatic hydrocarbons (PAH) that bind to aryl hydrocarbon receptors (AhRs) and decrease sperm production. Since it is not clear if AhR mediates DEP toxicity, we investigated the effect of DEPs in four strains of mice that have different AhR responsiveness. We treated BALB/c, C57BL/6, ICR and DBA/2 mice with DEP suspensions and compared their toxicity in each strain. In both the vehicle- and DEP-treated groups, ethoxyresorufin-O-deethylase (EROD) activity, as an indirect index of AhR activity, was increased in the order of BALB/c > C57BL/6 > ICR > DBA/2. Only BALB/c and C57BL/6 mice had significantly lower daily sperm production (DSP) than vehicle-treated mice. All strains exhibited increased sperm abnormalities. In particular, the C57BL/6, ICR and DBA/2 mice exhibited significantly increased abnormalities. A significant correlation was found between EROD activity and DSP or incidence of morphologically abnormal sperm. These data suggest that DEP toxicity may affect the male reproductive system in an AhR-dependent manner.
Izawa
Hiromi
H
Division of Human Sciences, Faculty of Health Sciences, Aomori University of Health and Welfare, Aomori, Japan. h_izawa@auhw.ac.jp
Kohara
Machiko
M
Watanabe
Gen
G
Taya
Kazuyoshi
K
Sagai
Masaru
M
D000818:Animals; D001835:Body Weight / Q000187:drug effects; D019363:Cytochrome P-450 CYP1A1 / Q000378:metabolism; D004822:Epididymis / Q000187:drug effects* / Q000378:metabolism; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D008811:Mice, Inbred DBA; D008813:Mice, Inbred ICR; D018336:Receptors, Aryl Hydrocarbon / Q000378:metabolism*; D013045:Species Specificity; D013094:Spermatozoa / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D013737:Testis / Q000187:drug effects* / Q000378:metabolism; D001335:Vehicle Emissions / Q000633:toxicity*