Lung maturation in the hyperinsulinemic rat fetus.
Hyperinsulinemic rat fetuses were obtained either by repeated in utero injections of long-acting insulin (resulting in fetal hypoglycemia) or by chronically infusing intravenous glucose to the mother (resulting in fetal hyperglycemia). Fetuses were examined at term. In insulin-injected fetuses (n = 15), surfactant (S) fraction phosphatidylcholine (PC) and disaturated phosphatidylcholine (DSPC) were significantly decreased (3.6 +/- 0.1 nmol Pi/mg tissue; p less than 0.001 and 2.8 +/- 0.1 nmol/mg; p less than 0.025, respectively) as compared with their saline-injected controls (4.8 +/- 0.2 and 3.3 +/- 0.1 nmol/mg, respectively, n = 19). However, residual (R) fraction was unchanged, and there was no difference in whole-lung phospholipids (combined S and R fractions). These results are consistent with morphological data showing a lower lamellar body area per type II cell profile in insulin-injected fetuses as compared with their controls [1.41 +/- 0.13 micron 2 (n = 72) versus 1.99 +/- 0.14 micron 2 (n = 129) p less than 0.01]. Glycogen content was slightly higher in insulin-injected fetuses (18.5 +/- 1.0 micrograms/mg, n = 17) than in their controls (15.1 +/- 0.8 micrograms/mg, n = 18; p less than 0.05). In the second model, changes in S fraction PC and DSPC were similar to those observed after insulin-injections: 4.3 +/- 0.25 and 3.4 +/- 0.2 nmol Pi/mg in fetuses of glucose-infused rats (n = 10) versus 5.7 +/- 0.45 and 4.3 +/- 0.3 nmol Pi/mg, respectively, in controls (n = 10, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Pignol
B
B
Bourbon
J
J
Ktorza
A
A
Marin
L
L
Rieutort
M
M
Tordet
C
C
D000818:Animals; D001786:Blood Glucose / Q000378:metabolism; D005314:Embryonic and Fetal Development; D005260:Female; D005333:Fetus / Q000378:metabolism*; D006943:Hyperglycemia / Q000378:metabolism; D006946:Hyperinsulinism / Q000378:metabolism* / Q000473:pathology; D007328:Insulin / Q000097:blood; D008168:Lung / Q000196:embryology / Q000378:metabolism*; D010743:Phospholipids / Q000378:metabolism; D011247:Pregnancy; D011663:Pulmonary Surfactants / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains
D001786:Blood Glucose; D007328:Insulin; D010743:Phospholipids; D011663:Pulmonary Surfactants