妊娠后期IUGR对蒙古绵羊胎儿肝脏糖代谢的影响

Effect of intrauterine growth restriction(IUGR) during late pregnancy on glucose metabolism in the fetal livers from Mongolian sheep

为了研究妊娠后期宫内生长受限对蒙古绵羊胎儿肝脏糖代谢能力的影响,试验采用健康的蒙古绵羊24只,经同期发情和同期受孕,选择6只在妊娠90天时进行屠宰。其余随机分为3组,限制1[0.18 MJ/(BW0.75·d),RG1]组、限制2[0.33 MJ/(BW0.75·d),RG2]组和自由采食[0.67 MJ/(BW0.75·d),CG]组,按各组能量水平进行饲养;至妊娠140天时屠宰,测定胎儿肝脏重、肝脏生长速率及肝脏、血液中的肝糖原、血糖、丙酮酸、乳酸等含量。结果表明:RG1组胎儿肝脏重(P<0.01)、肝脏生长速率(P<0.01)及肝脏中肝糖原含量(P<0.01)、丙酮酸含量(P<0.05)、乳酸含量(P<0.01)均低于CG组,而血液中丙酮酸含量(P<0.01)、乳酸含量(P<0.01)均高于CG组;RG2组胎儿肝脏重(P<0.05)、肝脏生长速率(P<0.05)、肝糖原含量(P<0.01)低于CG组,而血液中乳酸含量高于CG组(P>0.05)。说明妊娠后期宫内生长限制抑制了绵羊胎儿肝脏的生长发育,胎儿肝脏重和生长速率受到严重影响,肝糖原含量降低,糖异生能力增强,血液中乳酸和丙酮酸含量升高,胎儿肝脏糖代谢受到严重影响。

To study the effect of intrauterine growth restriction （IUGR） during late pregnancy on glucose metabolism in the fetal livers from Mon- golian sheep, 24 healthy Mongolian ewes were selected, which were treated with synchronization of estrus and conception. Six ewes were slaughtered at 9 d of pregnancy, and the others were randomly divided into three groups of nutritional levels, including restricted group 1 （RG1） with 0.18 MJ/（ BW^0.75·d）, restricted group 2 （RG2） with 0.33 MJ/（ BW^0.75·d）, and ad libitum- fed control group （CG） with 0.67 MJ/（ BW^0.75·d）. which were reared according the nutritional levels of each group. The ewes in each group were slaughtered at 140 d of pregnancy, and then their fetuses were removed for the determination of the weight and growth rate of the fetal livers as well as the contents of glycogen, blood glucose, pymvic acid, lactic acid and so on in the fetal livers and blood. The results showed that the weight and the growth rate of the fetal livers as well as, the contents of glycogen, and lactic acid of the fetal livers in the RG1 group were highly significantly lower （ P 〈 0.01 ） than those in the CG group, while the content of pyruic acid of the fetal livers in the RG1 group was significantly lower （ P 〈 0.05 ） than that in the CG group. However, the contents of pyruvic acid and lactic acid of the fetal blood in the RG1 group were highly higher than those in the CG group. The weight and growth rate of the fetal livers in the RG2 group were significantly lower （ P 〈 0.05 ） than those in the CG group, while the content of glycogen of the fetal livers in the RG2 group was highly significantly lower than that in the CG group（ P 〈 0.01 ）. However, the content of lactic acid of the fetal blood in the RG2 group was higher than that in the CG group（ P 〉 0.05 ）. The results indicate that the growth and development of fetal livers are inhibited by intrauterine growth restriction （IUGR） during late pregnancy, and the weight and growth rate of the fetal livers are severely affected. Meanwhile, the content of glycogen is decreased, and the capability of gluconeogenesis is strengthened, and the contents of lactic acid and pyruvic acid in fetal blood are increased, and glucose metabolism is severely affected in fetal liver.