Transport of amino acids through the placenta and their role.
Amino acids are transported across the human placenta mediated by transporter proteins that differ in structure, mechanism and substrate specificity. Some of them are Na+-dependent systems, whereas others are Na+-independent. Among these there are transporters composed of a heavy chain, a glycoprotein, and a light chain. Moreover, they can be differently distributed in the two membranes forming the syncytiotrophoblast. The transport mechanisms involved and their regulation are only partially known. In the placenta itself, part of the amino acids is metabolized to form other compounds important for the fetus. This occurs for instance for arginine, which gives rise to polyamines and to NO. Interconversion occurs among few other amino acids Transport is altered in pregnancy complications, such as restricted fetal growth.
Grillo
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MA
Dipartimento di Medicina e Oncologia Sperimentale, Sezione di Biochimica, Università di Torino, Via Michelangelo 27, 10126 Torino, Italy. mariaangelica.grillo@unito.it
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D026905:Amino Acid Transport Systems / Q000737:chemistry / Q000378:metabolism*; D000596:Amino Acids / Q000737:chemistry / Q000378:metabolism* / Q000502:physiology*; D000818:Animals; D005260:Female; D006801:Humans; D008431:Maternal-Fetal Exchange / Q000502:physiology*; D010920:Placenta / Q000737:chemistry / Q000378:metabolism*; D011247:Pregnancy
D026905:Amino Acid Transport Systems; D000596:Amino Acids