McGrath K R, Nakamoto T
Ann Nutr Metab. 1985;29(6):374-80. doi: 10.1159/000176994.
The effects of methionine intubation via gastric needle on the growth of incisor and molar tooth germs in newborn rats were investigated. Upon delivery, the pups were divided into groups of 8 and randomly assigned to dams which were then randomly assigned to three groups. Then the pups were intubated in the stomach with (a) no methionine - group I, (b) 0.1 g methionine per 100 g body weight - group II, or (c) 0.2 g methionine - group III, from day 3 to day 13 on every other day. At day 15, the average body weights of pups among the three groups showed no difference statistically, though animals in group III showed a 17.5% mortality rate; there were no deaths in the other two groups. There was inadequate hair growth in some pups in group III. The weights of incisor and of molar tooth germs in group II were heavier than in groups I and III. The total hydroxyproline content of incisor tooth germs in group II was also greater than in the other groups, whereas there was no difference in molar tooth germs on this parameter among all groups. Collagen synthesis of both tooth germs was highest in group III compared to other groups. The total amount of calcium in both tooth germs showed no difference among groups, but values were consistently higher in group II. 45Ca uptake showed no difference among groups. The present results indicate that the amount of methionine received by growing pups alters the composition of developing tooth germs, but that incisor and molar tooth germs are affected differently.
研究了经胃针插管给予蛋氨酸对新生大鼠切牙和磨牙牙胚生长的影响。出生后，将幼崽分成每组8只，随机分配给母鼠，然后将母鼠随机分为三组。然后从第3天到第13天，每隔一天给幼崽经胃插管给予：(a) 不给予蛋氨酸——第一组，(b) 每100克体重给予0.1克蛋氨酸——第二组，或(c) 0.2克蛋氨酸——第三组。在第15天，三组幼崽的平均体重在统计学上无差异，尽管第三组动物的死亡率为17.5%；其他两组无死亡情况。第三组的一些幼崽毛发生长不足。第二组切牙和磨牙牙胚的重量比第一组和第三组重。第二组切牙牙胚的总羟脯氨酸含量也高于其他组，而在该参数上，所有组的磨牙牙胚之间无差异。与其他组相比，第三组两个牙胚的胶原蛋白合成最高。两组牙胚中的钙总量在各组间无差异，但第二组的值始终较高。45Ca摄取在各组间无差异。目前的结果表明，生长中的幼崽摄入的蛋氨酸量会改变发育中牙胚的组成，但切牙和磨牙牙胚受到的影响不同。
