Palmer R M, Thom A, Flint D J
Rowett Research Institute, Bucksburn, Aberdeen, UK.
J Endocrinol. 1996 Dec;151(3):395-400. doi: 10.1677/joe.0.1510395.
Growth and protein accretion were studied in maternal muscle and liver and in foetuses of rats on day 20 of pregnancy. In young rats, weighing 120 g at mating, muscle mass and protein content of three hind-limb muscles, soleus, plantaris and gastrocnemius, increased on average by 7% compared with non-pregnant controls although the rate of muscle protein synthesis was decreased. In mature rats, rates of muscle protein synthesis were also reduced on day 20 of pregnancy but no change in muscle mass was observed. Rates of liver protein synthesis and accretion were increased in the pregnant animals; the effect was larger in the young pregnant rat. Administration of an antibody to rat GH (anti-rGH) for 10 days to young pregnant rats reversed the effect on the same three maternal muscles and resulted in a 9-11% lower muscle mass and protein content, compared with control pregnant animals. In both young and mature dams serum IGF-I concentrations were halved on day 20 of pregnancy, a further small reduction was observed in response to anti-rGH. No significant change in serum insulin or corticosterone levels was observed. Anti-rGH treatment also reduced food intake but foetal weight at 20 days was significantly increased (14%). The effects on maternal muscle were not the result of loss of appetite associated with anti-GH administration as, in rats pair-fed to the intake of the anti-rGH group, maternal muscle and foetal weights were the same as in animals with food available ad libitum. The data suggest that the GH/IGF axis is involved in the partitioning of nutrients between the dam and the foetus.
在妊娠第20天，对大鼠的母体肌肉和肝脏以及胎儿的生长和蛋白质积累进行了研究。在交配时体重为120克的年轻大鼠中，与未怀孕的对照组相比，比目鱼肌、跖肌和腓肠肌这三块后肢肌肉的肌肉质量和蛋白质含量平均增加了7%，尽管肌肉蛋白质合成速率有所下降。在成熟大鼠中，妊娠第20天时肌肉蛋白质合成速率也降低，但未观察到肌肉质量的变化。怀孕动物的肝脏蛋白质合成和积累速率增加；在年轻怀孕大鼠中这种影响更大。给年轻怀孕大鼠注射抗大鼠生长激素（anti-rGH）抗体10天，可逆转对相同三块母体肌肉的影响，与对照怀孕动物相比，肌肉质量和蛋白质含量降低了9-11%。在年轻和成熟的母鼠中，妊娠第20天时血清IGF-I浓度均减半，对抗rGH的反应中还观察到进一步的小幅下降。未观察到血清胰岛素或皮质酮水平的显著变化。抗rGH治疗也减少了食物摄入量，但20天时胎儿体重显著增加（14%）。对母体肌肉的影响不是与抗GH给药相关的食欲不振的结果，因为在与抗rGH组摄入量配对喂养的大鼠中，母体肌肉和胎儿体重与自由采食的动物相同。数据表明，GH/IGF轴参与了母体和胎儿之间营养物质的分配。
