Effects of long-term hypoxemia on pituitary-adrenal function in fetal sheep.

@article{Murotsuki1996EffectsOL,
  title={Effects of long-term hypoxemia on pituitary-adrenal function in fetal sheep.},
  author={Jun Murotsuki and Robert Gagnon and Stephen G Matthews and John R. G. Challis},
  journal={The American journal of physiology},
  year={1996},
  volume={271 4 Pt 1},
  pages={
          E678-85
        }
}
To test the hypothesis that long-term hypoxemia causes premature activation of the fetal pituitary-adrenal function, we embolized the fetal side of the placenta in pregnant sheep and examined the changes in concentrations of immunoreactive adrenocorticotropic hormone (irACTH), cortisol, and prostaglandin E2 (PGE2) in fetal plasma, and levels and localization of proopiomelanocortin (POMC) mRNA in the pars distalis and the pars intermedia of the fetal pituitary. Twelve fetal sheep were studied (6… 
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56 Citations
Background Citations
14
Methods Citations
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Results Citations
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56 Citations

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Citation Type

Long-term hypoxia alters ovine fetal endocrine and physiological responses to hypotension.
TLDR
An enhanced cortisol response to hypotension in LTH fetuses is demonstrated that does not appear to be the result of an increase in negative feedback sensitivity of the hypothalamic-pituitary-adrenal axis.
Long-term hypoxia enhances proopiomelanocortin processing in the near-term ovine fetus.
TLDR
LTH results in enhanced POMC processing and/or release to ACTH and increased hypothalamic drive, and plasma concentrations of both ACTH precursor and ACTH1-39 were significantly elevated in LTH fetuses, whereas the ratio of plasma precursors to ACTh was significantly lower.
Plasma Adrenocorticotropin and Cortisol Concentrations during Acute Hypoxemia after a Reversible Period of Adverse Intrauterine Conditions in the Ovine Fetus During Late Gestation**This work was supported by the British Heart Foundation.
The present study determined the pituitary-adrenal responses to acute hypoxemia after a period of reversible adverse intrauterine conditions produced by partial compression of the umbilical cord for…
Leptin Alters Adrenal Responsiveness by Decreasing Expression of ACTH-R, StAR, and P450c21 in Hypoxemic Fetal Sheep
TLDR
The results indicate that leptin blunts adrenal responsiveness in the late gestation hypoxemic fetus, and this effect appears mediated by decreased adrenal ACTH-R, StAR, and P450c21 expression.
The relation of S100beta and metabolic and endocrine responses to acute fetal hypoxemia.
TLDR
Evaluation of S100beta may provide a valuable clinical tool in the assessment of fetal well-being in suspected complicated pregnancies and induced significant falls in PaO2 with increases in fetal plasma concentrations of ACTH, cortisol, catecholamines and NPY, and elevations in blood glucose and lactate.
Long-term hypoxia increases leptin receptors and plasma leptin concentrations in the late-gestation ovine fetus.
TLDR
The data suggest that leptin is a hypoxia-inducible gene in the ovine fetus and OB-R expression is altered by LTH, which may be responsible in part, for previously observed alterations in fetal hypothalamic-pituitary-adrenal function following LTH.
Effects of Chronic Placental Insufficiency on Brain Development in Fetal Sheep
TLDR
The results show that a prolonged period of placental insufficiency, resulting in moderate fetal hypoxemia during the last third of gestation, can affect neurodevelopmental processes that occur late in gestation such as myelination and growth of the cerebellum.
Effect of chronic hypoxemia on the regulation of nitric-oxide synthase in the fetal sheep brain.
Changes in surfactant-associated protein mRNA profile in growth-restricted fetal sheep.
TLDR
It is concluded that fetal growth restriction due to placental insufficiency is associated with alterations in fetal lung SP, suggesting enhanced lung maturation that was highly dependent on the degree of increase in fetal plasma cortisol levels.
Changes in surfactant-associated protein mRNA profile in growth-restricted fetal sheep.
TLDR
It is concluded that fetal growth restriction due to placental insufficiency is associated with alterations in fetal lung SP, suggesting enhanced lung maturation that was highly dependent on the degree of increase in fetal plasma cortisol levels.
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References

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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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TLDR
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