| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Department of Obstetrics and Gynaecology, Research Centre for Reproductive Health, University of Adelaide, Adelaide, 5005, South Australia, Australia
2 Obstetric and Gynaecology, Research Centre for Reproductive Health, University of Adelaide, Adelaide, South Australia, Australia
* To whom correspondence should be addressed. E-mail: claire.roberts{at}adelaide.edu.au.
Appropriate partitioning of nutrients between the mother and conceptus is a major determinant of pregnancy success, with placental transfer playing a key role. Insulin-like growth factors (IGFs) increase in the maternal circulation during early pregnancy and are predictive of fetal and placental growth. We have previously shown in the guinea pig that increasing maternal IGF abundance in early-mid pregnancy enhances fetal growth and viability near term. We now show that this treatment promotes placental transport to the fetus, fetal substrate utilisation and nutrient partitioning near term. Pregnant guinea pigs were infused with IGF-I, IGF-II (both 1mg/kg/day) or vehicle subcutaneously from days 20-38 of pregnancy (term=69 days). Tissue uptake and placental transfer of the non-metabolisable radioanalogues [3H]-methyl-D-glucose (MG) and [14C]-amino-isobutyric acid (AIB) in vivo was measured on day 62. Early pregnancy exposure to elevated maternal IGF-I increased placental MG uptake by over 70% (P=0.004), while each IGF increased fetal plasma MG concentrations by 40-50% (P<0.012). Both IGFs increased fetal tissue MG uptake (P<0.048), while IGF-I also increased AIB uptake by visceral organs (P=0.046). In the mother, earlier exposure to either IGF increased AIB uptake by visceral organs (P<0.014), while IGF-I also enhanced uptake of AIB by muscle (P=0.044) and MG uptake by visceral organs (P=0.016) and muscle (P=0.046). In conclusion, exogenous maternal IGFs in early pregnancy sustainedly increase maternal substrate utilisation, placental transport of MG to the fetus and fetal utilisation of substrates near term. This was consistent with the previously observed increase in fetal growth and survival following IGF treatment.
This article has been cited by other articles:
|
|
 |
|
  T. M. Sullivan, G. C. Micke, N. Perkins, G. B. Martin, C. R. Wallace, K. L. Gatford, J. A. Owens, and V. E. A. Perry Dietary protein during gestation affects maternal insulin-like growth factor, insulin-like growth factor binding protein, leptin concentrations, and fetal growth in heifers J Anim Sci, October 1, 2009; 87(10): 3304 - 3316. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Gruslin, C. E. Cesta, M. Bell, Qing Qiu, M. A. Petre, and A. C. Holloway Effect of Nicotine Exposure During Pregnancy and Lactation on Maternal, Fetal, and Postnatal Rat IGF-II Profile Reproductive Sciences, September 1, 2009; 16(9): 875 - 882. [Abstract] [PDF]
|
|
|
|
 |
|
 A. L. Fowden, A. N. Sferruzzi-Perri, P. M. Coan, M. Constancia, and G. J. Burton Placental efficiency and adaptation: endocrine regulation J. Physiol., July 15, 2009; 587(14): 3459 - 3472. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
P. M. Coan, E. Angiolini, I. Sandovici, G. J. Burton, M. Constancia, and A. L. Fowden Adaptations in placental nutrient transfer capacity to meet fetal growth demands depend on placental size in mice J. Physiol., September 15, 2008; 586(18): 4567 - 4576. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
