Immunohistochemical characteristics of porcine intrahepatic nerves under physiological conditions and after bisphenol A administration.

Background: The neurochemistry of hepatic nerve fibres was investigated in large animal models after dietary exposure to the endocrine disrupting compound known as bisphenol A (BPA).
Materials and Methods: Antibodies against neuronal peptides were used to study changes in hepatic nerve fibres after exposure to BPA at varying concentrations using standard immunofluorescence techniques. The neuropeptides investigated were substance P (SP), galanin (GAL), pituitary adenylate cyclase activating polypeptide (PACAP), calcitonin gene regulated peptide (CGRP) and cocaine and amphetamine regulated transcript (CART). Immunoreactive nerve fibres were counted in multiple sections of the liver and among multiple animals at varying exposure levels. The data was pooled and presented as mean ± standard error of the mean.
Results: It was found that all of the nerve fibres investigated showed upregulation of these neural markers after BPA exposure, even at exposure levels currently considered to be safe. These results show very dramatic increases in nerve fibres containing the above-mentioned neuropeptides and the altered neurochemical levels may be causing a range of pathophysiological states if the trend of over-expression is extrapolated to developing humans.
Conclusions: This may have serious implications for children and young adults who are exposed to this very common plastic polymer, if the same trends are occurring in humans.