Effects of developmental exposure to bisphenol A on spatial navigational learning and memory in rats: A CLARITY-BPA study

• Published in: Hormones and behavior Vol. 80; pp. 139 - 148
• Main Authors: Johnson, Sarah A., Javurek, Angela B., Painter, Michele S., Ellersieck, Mark R., Welsh, Thomas H., Camacho, Luísa, Lewis, Sherry M., Vanlandingham, Michelle M., Ferguson, Sherry A., Rosenfeld, Cheryl S.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.04.2016; Elsevier BV
• Subjects: Animal cognition; Animal memory; Animals; Barnes maze; Behavioral testing; Benzhydryl Compounds - toxicity; Bisphenol A; DOHaD; Dose-Response Relationship, Drug; Endocrine disrupting chemicals; Estrogens; Estrogens, Non-Steroidal - toxicity; Ethinyl Estradiol - pharmacology; Female; Humans; Male; Maze Learning - drug effects; Phenols - toxicity; Pregnancy; Prenatal Exposure Delayed Effects; Rats; Rats, Sprague-Dawley; Rodents; Spatial Learning - drug effects; Spatial Memory - drug effects; Spatial Navigation; Testosterone; Behavioral testing; Testosterone; DOHaD; Estrogens; Rodents; Barnes maze; Endocrine disrupting chemicals
• ISSN: 0018-506X; 1095-6867
• DOI: 10.1016/j.yhbeh.2015.09.005

Bisphenol A (BPA) is a ubiquitous industrial chemical used in the production of a wide variety of items. Previous studies suggest BPA exposure may result in neuro-disruptive effects; however, data are inconsistent across animal and human studies. As part of the Consortium Linking Academic and Regulatory Insights on BPA Toxicity (CLARITY-BPA), we sought to determine whether female and male rats developmentally exposed to BPA demonstrated later spatial navigational learning and memory deficits. Pregnant NCTR Sprague–Dawley rats were orally dosed from gestational day 6 to parturition, and offspring were directly orally dosed until weaning (postnatal day 21). Treatment groups included a vehicle control, three BPA doses (2.5μg/kg body weight (bw)/day—[2.5], 25μg/kg bw/day—[25], and 2500μg/kg bw/day—[2500]) and a 0.5μg/kg/day ethinyl estradiol (EE)-reference estrogen dose. At adulthood, 1/sex/litter was tested for seven days in the Barnes maze. The 2500 BPA group sniffed more incorrect holes on day 7 than those in the control, 2.5 BPA, and EE groups. The 2500 BPA females were less likely than control females to locate the escape box in the allotted time (p value=0.04). Although 2.5 BPA females exhibited a prolonged latency, the effect did not reach significance (p value=0.06), whereas 2.5 BPA males showed improved latency compared to control males (p value=0.04), although the significance of this result is uncertain. No differences in serum testosterone concentration were detected in any male or female treatment groups. Current findings suggest developmental exposure of rats to BPA may disrupt aspects of spatial navigational learning and memory. •Male and female rats were pre and postnatally exposed to EE or 1 of 3 BPA doses.•They were tested as adults (90 to 120days of age) in the Barnes maze.•2500 BPA females were less likely to locate the escape box than control females.•2.5 BPA females showed prolonged latency, but effects did not reach significance.•Early BPA exposure may disrupt aspects of spatial navigational learning and memory.