Intrauterine Growth Retardation And Insulin Resistance

【Objective】 To investigate the factors related to the fetal growth and the levels of insulin (INS), glucose (Glu) and lipid of the maternal and cord blood. 【Methods】 According to the birth weight and gestational age, there were 20 mothers with small for gestational age (SGA) babies, 27 mothers with appropriate for gestational age (AGA) babies and 21 mothers with large for gestational age (LGA) babies to be studied, who all were delivered by cesarean section. The heights, weights before the pregnancy and the weights before the delivery of the mothers were also recorded. The birth weights, birth lengths and head circumferences of the newborns were collected within 12 hours postnatally. The levels of the INS were measured by ELISA and the concentrations of Glu were tested by the glucose oxidase-peroxidase method. An automatic biochemical apparatus was used to measure the levels of triglycerides (TG) and cholesterol (CHOL) in the blood. 【Results】 (1) The body mass index before the pregnancy in the mother with their SGA babies were significant lower than that in the mothers with AGA and LGA babies (P<0.05). And the maternal weight gains during the pregnancy in the mothers with LGA babies were much greater than the other two groups (P<0.05); (2) The average levels of the plasma insulin of the mothers among the three groups were 5.10mIU/L, 5.17 mIU/L, 8.81 mIU/L. The mean values of the plasma insulin in the SGA and AGA cord blood were 4.02 mIU/L, 5.94 mIU/L, 10.78 mIU/L respectively. The levels of insulin in the mother and LGA neonates were significant higher than those in the AGA and SGA groups(p<0.05), but there were no significant differences of the levels of INS between the groups of SGA and AGA; The levels of TG in the blood of the mothers with LGA babies (5.14mmol/L) were significant higher than those in the mothers with SGA (3.63mmol/L) and AGA (3.47 mmol/L) babies (P<0.05). The levels of TG in the blood of the mothers with SGA and AGA were similar. The mean level of TG in the cord blood of the SGA babies (0.52 mmol/L) was significant higher than that in the AGA babies (0.39 mmol/L) (p=0.026) and LGA babies (0.34 mmol/L) (P=0.003). There were also no significant differences of the concentration of Glu and CHOL of blood in the mothers and the neonates. (3) The levels of INS, TG, Glu and CHOL in the cord blood were not correlated with those in the maternal blood . There was no relationship between the INS levels in the cord blood and the birth weights, birth length and head circumferences. The heights, body mass index of the mothers before the pregnancy and the weight gains during the pregnancy were correlated positively with the birth weights of the newborns. 【Conclusions】 (1) There was no relationship between the levels of INS, Glu, TG, CHOL in the maternal and cord blood, showing that the endocrine system of the fetus are independent from the mothers'. The levels of TG in the cord blood of SGA were higher, which may indicatelipid metabolic dysfunction; The hyperinsulinemia in the LGA babies could be prolonged to the postnatal life. (2) The levels of INS in the cord blood did not correlated with the birth weights; (3) The maternal nutrition status before and during pregnancy is still one of the important factors for the fetal growth. It is very important for the mothers to get appropriate nutrition and weight gain during pregnancy to prevent the incidence of SGA and LGA. PART TWO THE MECHANISMS OF THE INSULIN SENSITIVITY ON THE ADULT MALE RATS WITH IUGR 【Objective】To demonstrate the endocrine functions of the islet βcells and insulin sensitivity in the male rats with intrauterine growth retardation (IUGR) induced by the starvation of the mothers during pregnancy; To investigate the effects of maternal starvation on the expressions of insulin receptor (IR), insulin receptor substrate-1(IRS-1), insulin receptor subtrate-2(IRS-2), phosphatidyl inositol 3-kinse(PI3K), insulin-like growth factor-1(IGF-1) of the livers in their adult male offspring. 【Methods】(1) Timed matings were performed in Wi...