Effects of methoxychlor on the reproductive system of the adult female mouse: 2. Ultrastructural observations.
Reprod Toxicol 1992 Jan; 6(1):93-98
The ultrastructure of different cellular compartments of the adult ovary in mice exposed to the pesticide methoxychlor (72435) (MXC), was investigated in order to assess subcellular toxic effects and their relevance, if any, to lowered reproductive capacity. Virgin female adult CD-1-mice were treated with estradiol-17beta (50282) (E- 17b) or MXC at a dose approximately equivalent to 200 mg/kg. Controls were treated with sesame-oil. Five consecutive days of exposure were followed by 2 days of no treatment to mimic a regular 5 day work week. At 24 hours after the last exposure, animals were killed and ovaries were processed for electron microscopy. Ultrastructural changes were evaluated, with atresia being assessed according to the method of Gondos. Steroid secreting interstitial cells of the ovaries in sesame-oil treated controls had little granular endoplasmic reticulum (RER) and extensive smooth endoplasmic reticulum (SER). The amount of lipid present in these cells, of both MXC and E-17b treated mice, far exceeded that in controls. Theca cells which also produce steroids, contained excessive RER and minimal SER, indicating a reduction in steroidogenesis, in both E-17b and MXC treated animals, confirming the estrogen like effects of MXC. The authors conclude that the ovary of the adult nonpregnant female is the target organ for MXC effects, the result of which appears to be a blockage of steroid biosynthesis.
NIOSH-Publication; NIOSH-Grant; Reproductive-system-disorders; Organo-chlorine-compounds; Chlorinated-hydrocarbon-pesticides; Cytotoxicity; Estrogenic-hormones; Histopathology; Laboratory-animals; Reproductive-hazards
Anatomy Louisiana State University 1542 Tulane Avenue New Orleans, LA 70112
Louisiana State University, School of Medicine, Department of Anatomy, New Orleans, Louisiana