The Inhibin B (InhB) Response to the Testicular Toxicants Mono-2-Ethylhexyl Phthalate (MEHP), 1,3 Dinitrobenzene (DNB), or Carbendazim (CBZ) Following Short-term Repeat Dosing in the Male Rat
Article first published online: 24 JAN 2013
© 2013 Wiley Periodicals, Inc.
Birth Defects Research Part B: Developmental and Reproductive Toxicology
Special Issue: Part B: Developmental and Reproductive Toxicology
Volume 98, Issue 1, pages 72–81, February 2013
How to Cite
Breslin, W. J., Paulman, A., Sun-Lin, D., Goldstein, K. M. and Derr, A. (2013), The Inhibin B (InhB) Response to the Testicular Toxicants Mono-2-Ethylhexyl Phthalate (MEHP), 1,3 Dinitrobenzene (DNB), or Carbendazim (CBZ) Following Short-term Repeat Dosing in the Male Rat. Birth Defects Research Part B: Developmental and Reproductive Toxicology, 98: 72–81. doi: 10.1002/bdrb.21043
- Issue published online: 5 FEB 2013
- Article first published online: 24 JAN 2013
- Manuscript Accepted: 12 DEC 2012
- Manuscript Received: 5 DEC 2012
- Inhibin B;
- testis histopathology;
- circulating biomarker;
- Sertoli cell
The objective of this study was to evaluate the utility of plasma Inhibin B (InhB) as a biomarker of testicular injury in adult rats following short-term exposure to the known Sertoli cell toxicants mono-2-ethylhexyl phthalate (MEHP), 1,3 dinitrobenzene (DNB), or carbendazim (CBZ).
Following oral gavage administration of the compounds for 2 or 7 days, the rats were evaluated for clinical signs, body weight, food consumption, organ weights, plasma hormone levels, and gross and microscopic pathology.
MEHP, DNB, and CBZ produced a range of testicular toxicity characterized by minimal exfoliation of germ cells as demonstrated by increased cellular debris in the epididymis (MEHP) to more severe and dose/duration responsive Sertoli cell vacuolation, germ cell degeneration, and multinucleated giant cells of germ cell origin (DNB and CBZ). The slight to moderate Sertoli and germinal cell injuries did not correlate with significant changes in plasma InhB levels following 2- or 7-day exposures. However, more severe injury to germinal epithelium following up to 7 days of exposure, but not after 2 days of exposure, correlated with decreased plasma InhB levels and less consistently with increases in plasma follicle stimulating hormone.
In conclusion, under the conditions of these studies, changes in InhB were not an effective early onset marker of testicular toxicity or an effective marker for slight to moderate levels of acute injury, and only reflected more severe disruption of spermatogenesis. Changes in plasma InhB and follicle stimulating hormone were poorly correlated except in some instances of moderate to marked testicular toxicity.