Foà A, Bertolucci C, Marsanich A, Innocenti A
Dipartimento di Biologia, Università di Ferrara, Italy.
Behav Neurosci. 1997 Oct;111(5):1123-32. doi: 10.1037//0735-7044.111.5.1123.
Pinealectomized lizards (Podarcis sicula) whose locomotor rhythms were recorded in constant temperature (29 degrees C) and darkness were subdivided into 2 groups of hosts: Each belonging to the 1st group (experimentals) received from a donor a pineal gland, and each belonging to the 2nd one (controls) received a piece of cerebellum. Pineal transplantation induced drastic changes in the free-running period (tau) of locomotor rhythms, which were significantly greater than the tau changes induced by cerebellum transplantation. Either application or removal of melatonin implants left the locomotor rhythms of the controls completely undisturbed, showing that in absence of melatonin rhythms (pinealectomy alone abolishes blood-borne melatonin rhythms) melatonin implants are ineffective. Melatonin rhythms, however, had to be present in the experimentals, because the circadian system reacts to melatonin implants by changing tau (as if melatonin rhythms had been suppressed) and to removal of the implants by again changing tau (as if melatonin rhythms had been restored).
对松果体切除的蜥蜴(意大利壁蜥)进行实验,将其置于恒温(29摄氏度)黑暗环境中并记录其运动节律,然后将这些蜥蜴分为两组宿主:第一组(实验组)每只从供体接受一个松果体,第二组(对照组)每只接受一块小脑。松果体移植导致运动节律的自由运行周期(tau)发生剧烈变化,这种变化明显大于小脑移植引起的tau变化。无论是植入还是移除褪黑素,对照组的运动节律都完全不受影响,这表明在没有褪黑素节律的情况下(仅松果体切除就会消除血液中的褪黑素节律),褪黑素植入无效。然而,实验组必须存在褪黑素节律,因为昼夜节律系统会通过改变tau对褪黑素植入做出反应(就好像褪黑素节律被抑制了一样),并通过再次改变tau对移除植入物做出反应(就好像褪黑素节律被恢复了一样)。