Fructose-1,6-diphosphatase and glucose-6-phosphatase in newborn rats with intrauterine growth retardation.
The activities of two gluconeogenic enzymes, glucose-6-phosphatase and fructose-1,6-diphosphatase were examined in the normal and intrauterine growth retarded (IUGR) rat during the first 5 days of life. The fructose-1,6-diphosphatase activity, 1.54 +/- 0.10 mumol/min/g liver (means +/- SEM) in control and 1.47 +/- 0.20 in the IUGR rats, increased in both groups on days 2--4 but remained significantly lower in the IUGR rats through day 4 (4.53 +/- 0.6 mumol/min/g liver in control and 3.09 +/- 0.22 mumul/min/g liver in the IUGR rats, P less than 0.01). The glucose-6-phosphatase activity increased similarly in both groups. The weight of the IUGR rats remained lower through the third postnatal day (6.47 +/- 0.42 compared to 8.64 +/- 0.27 g in control rats). Blood glucose concentrations at birth were 117 +/- 11 mg/dl in control rats and 73 +/- 11 mg/dl in the IUGR rats (P less than 0.01). Although the glucose concentrations increased in both groups on days 2--4, the IUGR rats maintained relatively lower levels (P less than 0.01). The results indicate that IUGR fetal rats do not have augmented gluconeogenesis in spite of hypoglycemia. In addition, effective gluconeogenesis in the neonatal period appears to be delayed.
D000818:Animals; D000831:Animals, Newborn; D001786:Blood Glucose / Q000378:metabolism; D001835:Body Weight; D005260:Female; D005317:Fetal Growth Retardation / Q000201:enzymology*; D005635:Fructosediphosphates / Q000378:metabolism*; D005943:Gluconeogenesis; D005952:Glucose-6-Phosphatase / Q000378:metabolism*; D006598:Hexosediphosphates / Q000378:metabolism*; D008099:Liver / Q000378:metabolism*; D008954:Models, Biological; D011247:Pregnancy; D051381:Rats
D001786:Blood Glucose; D005635:Fructosediphosphates; D006598:Hexosediphosphates; D005952:Glucose-6-Phosphatase