Effects of fetal hypoinsulinemia on fetal hepatic insulin binding in the rat.
Fetal hepatic insulin binding was studied in term fetal rats born to control mothers, mothers fasted for 48 h and mothers made hyperinsulinemic by the chronic, exogenous administration of insulin for 5 days prior to term. Maternal hyperinsulinemia was associated with fetal hypoglycemia and an approx. 70% reduction in fetal plasma insulin. Fetuses from these mothers exhibited an increase in hepatic insulin binding as indicated by a significant change in Scatchard analyses. No significant effect on fetal hepatic insulin binding by Scatchard analysis was seen with maternal fasting, despite a modest decrease in fetal plasma insulin. However, analysis of all animals showed that high-affinity fetal hepatic insulin binding and specific 125I-insulin binding were inversely correlated with fetal plasma insulin concentration. These results indicate that fetal rat liver, similar to adult rat liver, responds to a decrease in circulating insulin to below normal concentrations with an increase in insulin receptor binding.
Gruppuso
P A
PA
Section of Biochemistry, Brown University, Providence, RI 02903.
D000818:Animals; D005215:Fasting; D005260:Female; D005312:Fetal Blood / Q000378:metabolism*; D006946:Hyperinsulinism / Q000097:blood*; D007328:Insulin / Q000097:blood*; D007700:Kinetics; D008099:Liver / Q000196:embryology* / Q000378:metabolism; D008431:Maternal-Fetal Exchange; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D011972:Receptor, Insulin / Q000378:metabolism*; D012016:Reference Values
D007328:Insulin; D011972:Receptor, Insulin