Bull J S, Grundy D, Scratcherd T
J Physiol. 1985 Oct;367:353-62. doi: 10.1113/jphysiol.1985.sp015828.
The effect of D- and L-isomers of tryptophan and phenylalanine on fasting motor activity of canine jejunum were investigated. Only L-tryptophan had any effect on jejunal motility. The concentration of L-tryptophan required to elicit a motor effect in 50% of animals was estimated at 28 mM. 50 mM-L-tryptophan stimulated jejunal motility after a latency of 4.5 +/- 0.7 min. The pattern of motility was similar to that evoked by feeding but continued for only 41 +/- 5 min and failed to disrupt the normal timing of the interdigestive migrating motor complex (m.m.c.). The duration of the subsequent phase II of the complex was, however, significantly reduced. Multiple infusion of L-tryptophan also failed to disrupt the timing of the m.m.c. These data are consistent with the hypothesis that specific breakdown components of protein digestion are implicated in the stimulation of postprandial motor activity. The mechanisms involved in the motor response to L-tryptophan are discussed.
研究了色氨酸和苯丙氨酸的D-异构体和L-异构体对犬空肠禁食运动活性的影响。只有L-色氨酸对空肠运动有影响。估计在50%的动物中引起运动效应所需的L-色氨酸浓度为28 mM。50 mM-L-色氨酸在4.5±0.7分钟的潜伏期后刺激空肠运动。运动模式与进食引起的相似，但仅持续41±5分钟，并且未能扰乱消化间期移行运动复合波（m.m.c.）的正常时间。然而，该复合波随后的II期持续时间显著缩短。多次输注L-色氨酸也未能扰乱m.m.c.的时间。这些数据与蛋白质消化的特定分解成分参与餐后运动活性刺激的假说一致。讨论了对L-色氨酸运动反应所涉及的机制。
