Intrauterine growth retardation is associated with reduced cell cycle activity, but not myofibre number, in ovine fetal muscle
Intrauterine growth retardation is associated with reduced cell cycle activity, but not myofibre number, in ovine fetal muscle
复制标题
DOI：
10.1071/rd99054
复制
发表时间：
1999-01-01
影响因子：
1.9
通讯作者：
Bell, AW
中科院分区：
文献类型：
--
作者：
Greenwood, PL;Slepetis, RM;Bell, AW
研究了妊娠85天绵羊胎儿肌肉细胞的发育。在100、115和130天时比较了大胎儿和小胎儿，并在母体营养不良7天后研究了另一组130天的大胎儿。腓骨长肌的肌生成在妊娠100 ~ 115天完成，肌纤维数量在小胎儿和大胎儿之间没有差异。在85天的胎儿中，被鉴定为进入细胞周期S期的肌纤维相关细胞核的比例为每小时1.7%。在大胎中，随后的速率相对恒定（约为1.5% h（-1）），而在小胎中，细胞周期活性随年龄下降，从1.3至0.9% h（-1），在130天的限制性母羊胎儿中为0.5% h（-1）。大胎儿细胞周期活动的恒定速率与肌肉生长的估计速率增加有关（腓骨长肌（mg）= 0.831 x 10（（0.024 x年龄[d]）），r（2）= 0.98），这与小胎儿缓慢且相对恒定的肌肉增长形成对比（8.4 mg/天（-1）），限制性母羊的大胎儿在130天时肌肉增长较慢。半膜肌中DNA和RNA含量的差异随年龄的增长而增加，130天时，大胎儿比小胎儿多70%的肌肉DNA，108%的肌肉RNA和104%的肌肉（均P
Cellular development of muscle was studied in sheep fetuses at 85 days of gestation. Large and small fetuses were compared at 100, 115 and 130 days, and an additional group of large 130-day fetuses were studied following 7 days of maternal undernutrition. Myogenesis in the peroneus longus muscle was completed between 100 and 115 days of gestation, and myofibre number did not differ between small and large fetuses. The proportion of myofibre-related nuclei identified as entering S-phase of the cell cycle was 1.7% per hour in 85-day fetuses. In large fetuses, subsequent rates were relatively constant (approximate to 1.5% h(-1)), whereas in small fetuses cell cycle activity declined with age from 1.3 to 0.9% h(-1), and was 0.5 % h(-1) in 130-day fetuses of restricted ewes. The constant rate of cell cycle activity in large fetuses was associated with an increasing estimated rate of muscle growth (peroneus longus (mg) = 0.831 x 10((0.024 x age [d])), r(2) = 0.98), which contrasted with slow and relatively constant muscle accretion in small fetuses (8.4 mg day(-1)), and slower muscle accretion at 130 days in large fetuses from restricted ewes. Differences in DNA and RNA content in the semimembranosus muscle increased with age, large fetuses having 70% more muscle DNA, 108% more muscle RNA and 104% larger muscles than small fetuses at 130 days (all P