Effects of isulin-like growth factor-I on maternal and fetal plasma amino acid levels in pregnant rats.
Pregnant rats were subcutaneously administered with recombinant human insulin-like growth factor-I (rhIGF-I) in doses of 0 (control), 1, 2, and 4 microg/g body weight per day from day 18 to 21 of pregnancy. On day 21 of pregnancy, maternal and fetal plasma samples were collected and those amino acid levels were measured. The ratios of fetal/maternal plasma amino acids, especially leucine, isoleucine, tryptophan, phenylalanine and tyrosine, increased in 2 microg rhIGF-I treated group. Both total fetal weight and total placental weight were also higher than those in the control group. These results suggested that IGF-I enhanced fetal growth by, as one of its possible mechanisms, promoting placental amino acid supplies from the mother to fetuses.
Thongsong
Boonrit
B
Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.
Bonkobara
Makoto
M
Matsumoto
Mitsuhito
M
Jang
Jong-Sik
JS
Matsuki
Naoaki
N
Inaba
Mutsumi
M
Ono
Kenichiro
K
D000596:Amino Acids / Q000097:blood*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D005314:Embryonic and Fetal Development / Q000187:drug effects; D005260:Female; D005333:Fetus / Q000098:blood supply* / Q000187:drug effects*; D007334:Insulin-Like Growth Factor I / Q000008:administration & dosage / Q000494:pharmacology*; D008431:Maternal-Fetal Exchange; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D015430:Weight Gain
D000596:Amino Acids; D007334:Insulin-Like Growth Factor I