Received December 29, 2005
Revised January 13, 2006
Accepted after revision January 13, 2006
Placental-Perinatal [275]
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Cortisol, aldosterone, and porcine conceptus development
Harold G. Klemcke 1*,
J L Vallet 2,
R K Christenson 2
1 U.S. Army Institute of Surgical Research
2 USDA Meat Animal Research Center
* To whom correspondence should be addressed. E-mail: harold.klemcke{at}amedd.army.mil.
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Abstract |
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A study was conducted to evaluate the influence of
maternal cortisol on early conceptus development in pigs
(Sus scrofa). The corticosteroid synthesis inhibitor
metyrapone was injected during days 14-19 of pregnancy,
without (n= 6) and with (n = 6) commensurate
administration of cortisol. Blood samples were taken via
an indwelling jugular catheter on days 14 and 18, and
conceptuses were collected during surgery on day 20.
Compared with vehicle injected control pigs (n = 7)
plasma cortisol and aldosterone concentrations were
decreased (P <0.01) 52% and 29% respectively by
metyrapone treatment. Cortisol administration reversed
decreases in plasma cortisol by day 18. There were no
treatment-associated effects on conceptus survival or
size. Nor were there treatment-associated effects on
allantoic fluid volume or content. Trophodermal
glucocorticoid receptor (GR) mRNA expression decreased 34
% (P < 0.05) in metyrapone treated pigs, and was not
further influenced by concomitant administration of
cortisol, thereby suggesting an influence of aldosterone
on GR mRNA expression. Also, when all pigs were
considered there were treatment-independent 2nd order
polynomial regressions (P < 0.05) between maternal plasma
cortisol concentrations and embryonic weight, allantoic
size, and allantoic glucose concentrations, and between
plasma aldosterone concentrations and trophodermal
GRmRNA expression. Such biphasic corticosteroid-
concentration vs tissue-measure curves are noteworthy,
but difficult to validly interpret. They may suggest that
an appropriate corticosteroid environment is necessary
for optimal porcine embryonic development during this
stage of gestation, but cannot overshadow the absence of
treatment effects on the porcine embryonic measures
evaluated.
Key Words:
Adrenal gland, Endocrinology, Fetal
