Younoszai M K
Am J Clin Nutr. 1984 Dec;40(6):1243-9. doi: 10.1093/ajcn/40.6.1243.
The absorption of L-valine was studied in segments of the jejunum and ileum using a one pass in situ perfusion technique in 1-, 2-, 3-, and 4-wk-old healthy control and in growth-retarded rats (suckled with mothers fed a protein-deficient diet and fed the same diet after weaning). In the jejunum of control rats, rate of absorption of L-valine declined from about 270 to 80 mumol/h per g mucosal weight, between 2 and 4 wk of life. At each age period, in both segments, rates of absorption of L-valine based on weight of the segments were significantly greater in the growth-retarded than in the control rats. However, based on length of the intestinal segments rates of absorption were similar in corresponding segments of the control and growth-retarded rats. These findings indicated that although the intestine in the growth-retarded rats was atrophic compared to that in control rats, the capability to absorb L-valine had been preserved, by increasing the rate of absorption per unit weight of intestine.
采用单通道原位灌注技术，对1周龄、2周龄、3周龄和4周龄的健康对照大鼠以及生长迟缓大鼠（由喂食蛋白质缺乏饮食的母鼠哺乳，断奶后也喂食相同饮食）空肠和回肠段中L-缬氨酸的吸收情况进行了研究。在对照大鼠的空肠中，L-缬氨酸的吸收速率在2至4周龄期间从约每克黏膜重量270微摩尔/小时降至80微摩尔/小时。在每个年龄段，在两个肠段中，基于肠段重量计算的生长迟缓大鼠L-缬氨酸吸收速率均显著高于对照大鼠。然而，基于肠段长度计算，对照大鼠和生长迟缓大鼠相应肠段的吸收速率相似。这些发现表明，尽管与对照大鼠相比，生长迟缓大鼠的肠道萎缩，但通过提高单位重量肠道的吸收速率，其吸收L-缬氨酸的能力得以保留。
