Changes in memory and synaptic plasticity induced in male rats after maternal exposure to bisphenol A

Toxicology. 2014 Aug 1:322:51-60. doi: 10.1016/j.tox.2014.05.001. Epub 2014 May 10.

Abstract

Bisphenol A (BPA), a component of polycarbonate and epoxy resins, has been reported to adversely impact the central nervous system, especially with respect to learning and memory. However, the precise effect and specific mechanisms have not been fully elucidated. In the present study, pregnant Sprague-Dawley rats were orally administered with BPA at 0.05, 0.5, 5 or 50mg/kg·body weight (BW) per day from embryonic day 9 (E 9) to E 20. We examined the effects of maternal BPA exposure on memory and synaptic structure in the hippocampus of male offspring at postnatal day (PND) 21. Maternal BPA exposure significantly affected locomotor activity, exploratory habits, and emotional behavior in open field test, and increased reference and especially working memory errors in the radial arm maze during the postnatal developing stage. Maternal BPA exposure had an adverse effect on synaptic structure, including a widened synaptic cleft, a thinned postsynaptic density (PSD), unclear synaptic surface and disappeared synaptic vesicles. Furthermore, maternal BPA exposure decreased the mRNA and protein expressions of synaptophysin, PSD-95, spinophilin, GluR1 and NMDAR1 in the hippocampus of male offspring on PND 21. These results showed that fetal growth and development was more sensitive to BPA exposure. The decreased learning and memory induced by maternal exposure to BPA in this study may be involved in synaptic plasticity alteration.

Keywords: Bisphenol A; Glutamate receptors; Learning and memory; Synaptic marker; Synaptic structural.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Behavior, Animal / drug effects
  • Benzhydryl Compounds / toxicity*
  • Blotting, Western
  • Estrogens, Non-Steroidal / toxicity*
  • Female
  • Gonadal Steroid Hormones / metabolism
  • Male
  • Maternal Exposure / adverse effects
  • Maternal-Fetal Exchange
  • Maze Learning / drug effects
  • Memory / drug effects*
  • Microscopy, Electron, Transmission
  • Motor Activity / drug effects
  • Nerve Tissue Proteins / biosynthesis
  • Nerve Tissue Proteins / genetics
  • Neuronal Plasticity / drug effects*
  • Phenols / toxicity*
  • Pregnancy
  • Prenatal Exposure Delayed Effects
  • RNA / biosynthesis
  • RNA / isolation & purification
  • Rats
  • Rats, Sprague-Dawley
  • Real-Time Polymerase Chain Reaction
  • Synapses / drug effects*
  • Synapses / ultrastructure

Substances

  • Benzhydryl Compounds
  • Estrogens, Non-Steroidal
  • Gonadal Steroid Hormones
  • Nerve Tissue Proteins
  • Phenols
  • RNA
  • bisphenol A