Bonouali-Pellissier S
Université de Savoie, Laboratoire de Physiologie et Pharmacologie Appliquées, Chambéry, France.
J Pineal Res. 1994 Sep;17(2):79-85. doi: 10.1111/j.1600-079x.1994.tb00117.x.
The aim of this study was to determine, in the rat, the interaction between melatonin and cholecystokinin in the regulation of the ileal interdigestive motility. This was analyzed by the chronic electromyography technique. Ileal motility was defined by the presence of intermittent spike bursts corresponding to the contractile activity of the organ. In control rats, these spike bursts were organized in cyclic myoelectrical complexes. Each complex is characterized by two successive spiking activity phases: the irregular phase (ISA) followed by the regular phase (RSA). Pinealectomy suppressed the RSA phase so ileal motility was constituted only by the ISA phase. When melatonin (1 mg/kg i.v.) was injected into pinealectomized rats, RSA phases were immediately and definitively restored. RSA phases were also re-established when the "alimentary" type of cholecystokinin receptors (CCKA) were blocked by selective antagonists such as L364,718 or SR27897 (1 mg/kg i.v.). The latter had better brain accessibility than L364,718. Unlike the effects of melatonin, the effect of these antagonists was neither immediate (the latency is longer for L364,718 than for SR27897) nor definitive. In control rats, cholecystokinin (5 micrograms/kg i.v.) induced a characteristic long-lasting (29 +/- 2 min) excitomotor effect on the ileum. This effect was suppressed in pinealectomized rats and was restored after melatonin treatment. These results suggest that, via the central nervous system, melatonin is involved in the modulation of cholecystokinin action on ileal motility.
本研究的目的是确定在大鼠中褪黑素与胆囊收缩素在回肠消化间期运动调节中的相互作用。通过慢性肌电图技术对此进行分析。回肠蠕动通过对应于该器官收缩活动的间歇性尖峰爆发来定义。在对照大鼠中，这些尖峰爆发组织成周期性肌电复合波。每个复合波的特征在于两个连续的尖峰活动阶段：不规则阶段（ISA），随后是规则阶段（RSA）。松果体切除抑制了RSA阶段，因此回肠蠕动仅由ISA阶段构成。当将褪黑素（1mg/kg静脉注射）注入松果体切除的大鼠时，RSA阶段立即并最终恢复。当“消化型”胆囊收缩素受体（CCKA）被选择性拮抗剂如L364,718或SR27897（1mg/kg静脉注射）阻断时，RSA阶段也得以重建。后者比L364,718具有更好的脑通透性。与褪黑素的作用不同，这些拮抗剂的作用既不立即（L364,718的潜伏期比SR27897长）也不持久。在对照大鼠中，胆囊收缩素（5μg/kg静脉注射）对回肠诱导出特征性的持久（29±2分钟）兴奋运动效应。在松果体切除的大鼠中该效应被抑制，而在褪黑素治疗后得以恢复。这些结果表明，通过中枢神经系统，褪黑素参与调节胆囊收缩素对回肠蠕动的作用。
