Ouichou A, Pévet P
URA-CNRS 1332 Neurobiologie des fonctions rythmiques et saisonnières, Université Louis Pasteur, Strasbourg, France.
Biol Signals. 1992 Mar-Apr;1(2):78-87. doi: 10.1159/000109313.
We have recently demonstrated that delta-sleep-inducing peptide (DSIP) stimulates indolamine secretion from rat pineal glands. In the present study, we show that tryptophan (TRP), as well as DSIP, stimulate melatonin (MEL) and 5-methoxy-tryptophol (5-ML) secretion in a dose-dependent manner between 5 x 10(-6) and 10(-4) M. The kinetic characteristics of the MEL and 5-ML secretion and the response induced by the two substances were similar. The increase in MEL secretion in response to 10(-4) M DSIP was completely inhibited by pretreatment of the pineals with 10(-5) M phenanthroline (amino-peptidase inhibitor), suggesting that stimulatory effect of DSIP was due to TRP liberated by peptide degradation. This mechanism occurring in the pineal was confirmed using 10(-4) M para-chlorophenylalamine (TRP hydroxylase inhibitor), which reduced the pineal response to 10(-4) and 10(-5) M DSIP by 50 and 100%, respectively.
我们最近证明，δ-睡眠诱导肽（DSIP）能刺激大鼠松果体分泌吲哚胺。在本研究中，我们发现色氨酸（TRP）以及DSIP在5×10⁻⁶至10⁻⁴M之间以剂量依赖方式刺激褪黑素（MEL）和5-甲氧基色醇（5-ML）的分泌。MEL和5-ML分泌的动力学特征以及这两种物质诱导的反应相似。用10⁻⁵M菲咯啉（氨基肽酶抑制剂）预处理松果体后，对10⁻⁴M DSIP的MEL分泌增加完全被抑制，这表明DSIP的刺激作用是由于肽降解释放的TRP所致。使用10⁻⁴M对氯苯丙氨酸（TRP羟化酶抑制剂）证实了松果体中发生的这一机制，它分别使松果体对10⁻⁴和10⁻⁵M DSIP的反应降低了50%和100%。
