Altered stress-induced cortisol levels in goats exposed to polychlorinated
biphenyls (PCB 126 and PCB 153) during fetal and postnatal development.
http://www.ncbi.nlm.nih.gov/pubmed/19184731
Zimmer KE, Gutleb AC, Lyche JL, Dahl E, Oskam IC, Krogenaes A, Skaare JU,
Ropstad E.
Department of Basic Sciences and Aquatic Medicine, Norwegian School of
Veterinary Science, Oslo, Norway. karin.zimmer@veths.no
Short-term stress exposure is associated with activation of the
hypothalamic-pituitary-adrenal (HPA) axis and a consequent rise in blood
glucocorticoids and catecholamines, from the adrenal cortex and medulla,
respectively. The HPA axis is a potential target for some persistent organic
pollutants, among which polychlorinated biphenyls (PCB) were found to be
modulators of the mammalian endocrine system. PCB are distributed globally
in the environment, in food chains, and are transferred to the fetuses of
pregnant animals and via mother's milk to suckling offspring. In the present
study it was postulated that intrauterine and lactational exposure to either
of two single congeners of PCB (PCB 153 and PCB 126, respectively) might
affect basal cortisol concentrations, and also the cortisol response to
short-term stress in adulthood. Thus, pregnant goats were orally exposed to
one of these PCB congeners from d 60 of gestation until delivery, and their
offspring studied. Low-dose exposure to PCB 153 and PCB 126 resulted in
significantly lower mean basal cortisol concentrations in goat offspring
during certain periods of pubertal development and their first breeding
season. Male goat kids exposed to either PCB congener showed a greater and
more prolonged rise in plasma cortisol levels than controls when animals
were subjected to mild stress at 9 mo of age using frequent blood sampling.
Neither the basal maternal cortisol plasma level nor goat kid adrenal masses
were affected by PCB exposure.
PMID: 19184731 [PubMed - in process]
