Citation:

Bodensteiner, K. J., H. R. Sawyer, C. L. Moeller, C. M. Kane, K. Pau, G R. Klinefelter, AND D. Veeramachaneni. CHRONIC EXPOSURE TO DIBROMOACETIC ACID, A WATER DISINFECTION BY-PRODUCT, DIMINISHES PRIMORDIAL FOLLICLE POPULATIONS IN THE RABBIT. TOXICOLOGICAL SCIENCES 80(1):83-91, (2004).

Impact/Purpose:

To determine if dibromoacetic acid (DBA) affects folliculogenesis

Description:

To determine if dibromoacetic acid (DBA) affects folliculogenesis, four groups of female Dutch-belted rabbits were exposed daily to 0, 1, 5, or 50 mg DBA/kg body wt. in drinking water beginning in utero from gestation day 15 throughout life. Functionality of the endocrine axis was assessed by measuring serum concentrations of gonadotropins following an intramuscular injection of 10 ug GnRH at 12 (prepubertal; N=6/dose group) and 24 (postpubertal; N=10/dose group) wk of age. A day after GnRH challenge, number of ovulation sites and ovarian weights were determined at necropsy. Left ovaries were processed for histopathology, serially sectioned at 6 um, and every twelfth section stained with hematoxylin and eosin was evaluated. All healthy follicles were categorized as primordial, primary, small preantral, large preantral, or small antral follicles. The area of each section evaluated was measured and the number of follicles in each category expressed per mm2 unit area. In prepubertal animals, DBA caused a reduction in the number of primordial follicles (p <0.05) and total health follicles (p<0.05) at the 50 mg/kg dose level. In adult animals, there were fewer primordial follicles in both the 5 (p <0.01) and 50 (p<0.1) mg/kg dose groups. No profound changes in gonadotropin profiles were observed. Although chronic exposure to DBA did not appear to have an effect on late follicular development or ovulation, DBA did reduce the population of primordial follicles. The long-term health consequences of diminished primordial follicles are unknown, but it is very likely that reproductive senescence would occur earlier.

Record Details: