Tissue concentrations of free amino acids in term human placentas

Philipps, Anthony F; Holzman, Ian R.; Teng, Cecilia; Battaglia, Frederick C.

doi:10.1016/s0002-9378(16)33136-2

Cited by 141 publications

(71 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In healthy fetuses, umbilical cord blood concentrations of most amino acids are significantly higher than maternal concentrations at mid gestation and term with the exception of aspartate and glutamate (Cetin et al, 1990;McIntosh et al, 1984;Philipps et al, 1978;Soltesz et al, 1985). Placental tissue concentrations of free amino acids appear to be higher than in both fetal and maternal plasma (Camelo et al, 2004;Philipps et al, 1978).…”

Section: Amino Acid Transportmentioning

confidence: 94%

See 1 more Smart Citation

Placental nutrient supply and fetal growth

Desforges¹,

Sibley²

2010

Int. J. Dev. Biol.

145

View full text Add to dashboard Cite

This review considers mechanisms by which transfer across the placenta takes place and how the capacity of the placenta to supply nutrients relates to fetal growth and vice versa. Blood flow through both uterine and umbilical circulations of the placenta, the structural properties of the placental exchange barrier and its related diffusional permeability, and the expression and activity of a wide range of transporter proteins in the syncytiotrophoblast, the transporting epithelium of the placenta, all need to be taken into account in considering placental supply capacity. We discuss the evidence that each of these factors affects, and is affected by, fetal growth rate and consider the regulatory mechanisms involved, with a particular focus on data that has emerged from study of the system A amino acid transporter. We consider that future work will build on the considerable foundation of knowledge regarding placental transfer mechanisms, as well as the other aspects of placental structure and function, to develop new diagnostic and therapeutic strategies for pregnancy complications, such as fetal growth restriction or overgrowth.

show abstract

Section: Amino Acid Transportmentioning

confidence: 94%

“…Placental tissue concentrations of free amino acids appear to be higher than in both fetal and maternal plasma (Camelo et al, 2004;Philipps et al, 1978). Energy is therefore required to transport amino acids into the syncytiotrophoblast against their concentration gradient.…”

Section: Amino Acid Transportmentioning

confidence: 98%

Placental nutrient supply and fetal growth

Desforges¹,

Sibley²

2010

Int. J. Dev. Biol.

145

View full text Add to dashboard Cite

show abstract

“…In general, fetal concentrations of amino acids are higher than those in the maternal circulation [106][107][108]. Study of placental amino acid metabolism has proven to be quite complex.…”

Section: Placental Amino Acid Transfer and Metabolismmentioning

confidence: 99%

“…The development of techniques using isotope tracers has allowed the study of the bidirectional flow of amino acids and has improved the understanding of placental transport and metabolism of amino acids [107,[112][113][114][115]. In the human placenta, the fetal endothelial and syncytiotrophoblast layers are the only two cell layers separating maternal blood from fetal blood.…”

Section: Placental Amino Acid Transfer and Metabolismmentioning

confidence: 99%

The pregnant sheep as a model for human pregnancy

2008

View full text Add to dashboard Cite

Successful outcome of human pregnancy not only impacts the quality of infant life and well-being, but considerable evidence now suggests that what happens during fetal development may well impact health and well-being into adulthood. Consequently, a thorough understanding of the developmental events that occur between conception and delivery is needed. For obvious ethical reasons, many of the questions remaining about the progression of human pregnancy can not be answered directly, necessitating the use of appropriate animal models. A variety of animal models exist for the study of both normal and compromised pregnancies, including laboratory rodents, non-human primates and domestic ruminants. While all of these animal models have merit, most suffer from the inability to repetitively sample from both the maternal and fetal side of the placenta, limiting their usefulness in the study of placental or fetal physiology under non-stressed in vivo conditions. No animal model truly recapitulates human pregnancy, yet the pregnant sheep has been used extensively to investigate maternal-fetal interactions. This is due in part to the ability to surgically place and maintain catheters in both the maternal and fetal vasculature, allowing repeated sampling from non-anesthetized pregnancies. Considerable insight has been gained on placental oxygen and nutrient transfer and utilization from use of pregnant sheep. These findings were often confirmed in human pregnancies once appropriate technologies became available. The purpose of this review is to provide an overview of human and sheep pregnancy, with emphasis placed on placental development and function as an organ of nutrient transfer.

show abstract

“…It stabilizes cell membranes, modulates intracellular calcium and exhibits antiinflammatory effect [37]. Taurine is the most represented (~10 mM) "amino acid" in human placenta [38]. It is required for metabolic processes in the trophoblast and for cytoprotection during fetal development, especially for the formation of the central nervous system [39].…”

Section: Fig 2 Electrophoresis and Densitometry Results Of Western mentioning

confidence: 99%