Abstract
To investigate the role of insulin in modulation of fetal amino acid metabolism, insulin infusions were performed in 10 chronically-catheterized fetal lambs. Fetal insulin infusion caused a dose related fall in the arterial blood concentrations of 13 of 15 amino acids studied as well as a 15-25% decrease in total amino acid concentration. Fetal lambs exhibited a biphasic response of umbilical total amino acid uptake when compared to fetal blood insulin concentration, i.e., at achieved fetal insulin concentrations <100 μU/ml, umbilical uptake of 9 specific amino acids as well as summed amino acid uptake from the umbilical circulation were depressed, but at insulin concentrations of 100-350 μU/ml, amino acid uptakes were similar to or above control values. Insulin infusion also caused a drastic diminution in the rate of fetal urea excretion. These findings suggest that insulin acts in the fetus to depress amino acid catabolism, thus altering amino acid extraction and uptake. Depressed protein catabolism with or without enhanced amino acid uptake would have the theoretical effect of stimulation of net protein synthesis with a shift toward use of nonprotein substrates for energy purposes.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 251-259 |
| Number of pages | 9 |
| Journal | Journal of Developmental Physiology |
| Volume | 13 |
| Issue number | 5 |
| State | Published - 1990 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Developmental Biology
- Physiology
Cite this
Insulin-induced alterations in amino acid metabolism in the fetal lamb. / Philipps, Anthony F; Rosenkrantz, T. S.; Lemons, J. A.; Knox, I.; Porte, P. J.; Raye, J. R.
In: Journal of Developmental Physiology, Vol. 13, No. 5, 1990, p. 251-259.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Insulin-induced alterations in amino acid metabolism in the fetal lamb
AU - Philipps, Anthony F
AU - Rosenkrantz, T. S.
AU - Lemons, J. A.
AU - Knox, I.
AU - Porte, P. J.
AU - Raye, J. R.
PY - 1990
Y1 - 1990
N2 - To investigate the role of insulin in modulation of fetal amino acid metabolism, insulin infusions were performed in 10 chronically-catheterized fetal lambs. Fetal insulin infusion caused a dose related fall in the arterial blood concentrations of 13 of 15 amino acids studied as well as a 15-25% decrease in total amino acid concentration. Fetal lambs exhibited a biphasic response of umbilical total amino acid uptake when compared to fetal blood insulin concentration, i.e., at achieved fetal insulin concentrations <100 μU/ml, umbilical uptake of 9 specific amino acids as well as summed amino acid uptake from the umbilical circulation were depressed, but at insulin concentrations of 100-350 μU/ml, amino acid uptakes were similar to or above control values. Insulin infusion also caused a drastic diminution in the rate of fetal urea excretion. These findings suggest that insulin acts in the fetus to depress amino acid catabolism, thus altering amino acid extraction and uptake. Depressed protein catabolism with or without enhanced amino acid uptake would have the theoretical effect of stimulation of net protein synthesis with a shift toward use of nonprotein substrates for energy purposes.
AB - To investigate the role of insulin in modulation of fetal amino acid metabolism, insulin infusions were performed in 10 chronically-catheterized fetal lambs. Fetal insulin infusion caused a dose related fall in the arterial blood concentrations of 13 of 15 amino acids studied as well as a 15-25% decrease in total amino acid concentration. Fetal lambs exhibited a biphasic response of umbilical total amino acid uptake when compared to fetal blood insulin concentration, i.e., at achieved fetal insulin concentrations <100 μU/ml, umbilical uptake of 9 specific amino acids as well as summed amino acid uptake from the umbilical circulation were depressed, but at insulin concentrations of 100-350 μU/ml, amino acid uptakes were similar to or above control values. Insulin infusion also caused a drastic diminution in the rate of fetal urea excretion. These findings suggest that insulin acts in the fetus to depress amino acid catabolism, thus altering amino acid extraction and uptake. Depressed protein catabolism with or without enhanced amino acid uptake would have the theoretical effect of stimulation of net protein synthesis with a shift toward use of nonprotein substrates for energy purposes.
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M3 - Article
C2 - 2286748
AN - SCOPUS:0025200570
VL - 13
SP - 251
EP - 259
JO - Journal of Developmental Physiology
JF - Journal of Developmental Physiology
SN - 0141-9846
IS - 5
ER -