Yuen, B. S. J. and Owens, P. C. and Symonds, M. E. and Keisler, D. H. and Mcfarlane, James R. and Kauter, Kathleen G. and McMillen, I. C. (2004) Effects of leptin on fetal plasma adrenocorticotropic hormone and cortisol concentrations and the timing of parturition in the sheep. Biology of Reproduction, 70 (6). pp. 1650-1657. ISSN 0006-3363
|HTML Citation||EndNote||Dublin Core||Reference Manager|
Full text not available from this archive.
Official URL: http://dx.doi.org/10.1095/biolreprod.103.025254
Identification Number or DOI: doi: 10.1095/biolreprod.103.025254
We investigated whether leptin can suppress the prepartum activation of the fetal hypothalamus-pituitary-adrenal (HPA) axis and delay the timing of parturition in the sheep. First, we investigated the effects of a 4-day intravascular infusion of recombinant ovine leptin (n = 7) or saline (n = 6) on fetal plasma adrenocorticotropic hormone (ACTH) and cortisol concentrations, starting from 136 days gestation (i.e., at the onset of the prepartum activation of the fetal HPA axis. The effects of a continuous intrafetal infusion of leptin (n = 7) or saline (n = 5) from 144 days gestation on fetal plasma ACTH and cortisol concentrations and the timing of delivery were also determined in a separate study. There was an increase in fetal plasma ACTH (P < 0.01) and cortisol (P < 0.001) concentrations when saline was infused between 136-137 and 140-141 days gestation. Plasma ACTH and cortisol concentrations did not rise, however, when leptin was infused during this period of gestation. When leptin was infused after 144 days gestation, there was no effect of a 4- to 5-fold increase in circulating leptin on fetal ACTH concentrations. In contrast, leptin infusion from 144 days gestation suppressed (P < 0.05) fetal plasma cortisol concentrations by around 40% between 90 and 42 h before delivery. There was no difference, however, in the length of gestation between the saline- and leptin-infused groups (saline infused, 150.2 ± 0.5 days; leptin infused, 149.8 ± 1.0 days). In saline-infused fetuses, there was a significant negative relationship between the plasma concentrations of cortisol (y) and leptin (x) between 138 and 146 days gestation (y = 81.4 - 7.7x, r = 0.38, P < 0.005). This study provides evidence for an endocrine negative feedback loop between leptin and the HPA axis in fetal life.
|Item Type:||Article (Commonwealth Reporting Category C)|
|Additional Information:||Permanent restricted access to paper due to publisher's copyright restrictions.|
|Uncontrolled Keywords:||adrenal; cortisol; leptin; pregnancy; animal experiment; corticotropin blood level; delivery; fetus; gestational age; hydrocortisone blood level; hypothalamus hypophysis adrenal system; negative feedback; nonhuman; pregnancy; sheep|
|Fields of Research (FOR2008):||06 Biological Sciences > 0606 Physiology > 060699 Physiology not elsewhere classified|
11 Medical and Health Sciences > 1116 Medical Physiology > 111699 Medical Physiology not elsewhere classified
|Socio-Economic Objective (SEO2008):||E Expanding Knowledge > 97 Expanding Knowledge > 970111 Expanding Knowledge in the Medical and Health Sciences|
|Deposited On:||02 May 2010 22:56|
|Last Modified:||25 Aug 2011 16:22|
Archive Staff Only: edit this record