Effects of prenatal ethanol exposure on regulation of basal hypothalamic-pituitary-adrenal activity and hippocampal 5-HT1A receptor mRNA levels in female rats across the estrous cycle.
Prenatal ethanol exposure, like other early adverse experiences, is known to alter hypothalamic-pituitary-adrenal (HPA) activity in adulthood. The present study examined the modulatory effects of the gonadal hormones on basal HPA regulation and serotonin Type 1A receptor (5-HT(1A)) mRNA levels in adult female rats prenatally exposed to ethanol (E) compared to that in females from pair-fed (PF) and ad libitum-fed control (C) conditions. We demonstrate, for the first time, long-lasting consequences of prenatal ethanol exposure for basal corticosterone (CORT) regulation and basal levels of hippocampal mineralocorticoid (MR), glucocorticoid (GR) and serotonin Type 1A (5-HT(1A)) receptor mRNA, as a function of estrous cycle stage: (1) basal CORT levels were higher in E compared to C females in proestrus but lower in E and PF compared to C females in estrus; (2) there were no differences among groups in basal levels of adrenocorticotropin (ACTH), estradiol or progesterone; (3) hippocampal MR mRNA levels were decreased in E compared to PF and C females across the estrus cycle, with the greatest effects in proestrus, whereas E (but not PF or C) females had higher hippocampal GR mRNA levels in proestrus than in estrous and diestrus; (4) 5-HT(1A) mRNA levels were increased in E compared to PF and C females in diestrus. That alterations were revealed as a function of estrous cycle stage suggests a role for the ovarian steroids in mediating the adverse effects of ethanol. Furthermore, it appears that ethanol-induced nutritional effects may play a role in mediating at least some of the effects observed. The resetting of HPA activity by early environmental events could be one mechanism linking early life experiences with long-term health consequences. Thus, changes in basal CORT levels, a shift in the MR/GR balance and alterations in 5-HT(1A) receptor mRNA could have important clinical implications for understanding the secondary disabilities, such as an increased incidence of depression, in children with FASD.
Sliwowska
J H
JH
Department of Cellular and Physiological Sciences, The University of the British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada. sliwowsk@interchange.ubc.ca
Lan
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Yamashita
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Halpert
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Viau
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Weinberg
J
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D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D001481:Basal Metabolism / Q000187:drug effects; D030762:Estrous Cycle / Q000097:blood / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism; D000431:Ethanol / Q000009:adverse effects / Q000097:blood / Q000494:pharmacology*; D005260:Female; D006624:Hippocampus / Q000378:metabolism*; D006854:Hydrocortisone / Q000097:blood; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D008297:Male; D010913:Pituitary-Adrenal System / Q000187:drug effects* / Q000378:metabolism / Q000503:physiopathology; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects / Q000235:genetics* / Q000378:metabolism / Q000503:physiopathology; D051381:Rats; D017207:Rats, Sprague-Dawley; D044282:Receptor, Serotonin, 5-HT1A / Q000235:genetics* / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear / Q000235:genetics / Q000378:metabolism
D018160:Receptors, Cytoplasmic and Nuclear; D044282:Receptor, Serotonin, 5-HT1A; D000431:Ethanol; D000324:Adrenocorticotropic Hormone; D006854:Hydrocortisone