Riley W W, Austic R E
Department of Poultry and Avian Sciences, Cornell University, Ithaca, New York 14853.
Poult Sci. 1989 Sep;68(9):1255-62. doi: 10.3382/ps.0681255.
The intestinal absorption of lysine and arginine in the chick was characterized using an in situ-ligated intestinal segment technique, and the influence of dietary electrolytes on their absorption was examined. Each amino acid, labeled with 14C and provided at a concentration of .5 mM, was introduced into the lumen of the small intestine of young chicks. Absorption was defined as disappearance of label from the lumen after 4 min. Lysine absorption was greater than arginine absorption in the duodenum and in the middle and distal small intestine. The Jmax values for absorption of lysine and arginine were 315.0 nmol/min and 112.0 nmol/min, whereas the respective Kt values were 2.3 mM and 2.0 mM. Maximal transport of lysine and arginine occurred at pH 6.0. Lysine absorption was depressed (P less than .05) at pH 5.0 and pH 8.0, whereas arginine absorption was depressed (P less than .05) only at pH 8.0. High dietary chloride (.89%) produced higher (P less than .05) lysine absorption than a high dietary level of potassium (1.81%). No effect (P greater than .05) of dietary electrolytes on arginine absorption was detected. These results indicate that the dietary balance of monovalent electrolytes, and, hence, acid-base balance, may influence the intestinal absorption of lysine.
采用原位结扎肠段技术对雏鸡赖氨酸和精氨酸的肠道吸收特性进行了研究，并考察了日粮电解质对其吸收的影响。将标记有14C且浓度为0.5 mM的每种氨基酸引入雏鸡小肠肠腔。吸收定义为4分钟后肠腔内标记物的消失。十二指肠以及小肠中部和远端的赖氨酸吸收大于精氨酸吸收。赖氨酸和精氨酸吸收的Jmax值分别为315.0 nmol/分钟和112.0 nmol/分钟，而各自的Kt值分别为2.3 mM和2.0 mM。赖氨酸和精氨酸的最大转运发生在pH 6.0时。在pH 5.0和pH 8.0时赖氨酸吸收降低（P＜0.05），而精氨酸仅在pH 8.0时吸收降低（P＜0.05）。高氯日粮（0.89%）比高钾日粮（1.81%）产生更高（P＜0.05）的赖氨酸吸收。未检测到日粮电解质对精氨酸吸收有影响（P＞0.05）。这些结果表明，单价电解质的日粮平衡以及酸碱平衡可能会影响赖氨酸的肠道吸收。
