Lauber J K, Vriend J
Department of Zoology, University of Alberta, Edmonton, Canada.
Gen Comp Endocrinol. 1989 Dec;76(3):414-20. doi: 10.1016/0016-6480(89)90137-8.
Melatonin was measured by radioimmunoassay in several genetic strains of Japanese quail. Plasma melatonin (PM), measured at the nighttime peak, was highest in wild type quail reared on a diurnal lighting schedule; this PM peak was suppressed in continuous light. Albino quail had low melatonin levels, whether reared under diurnal conditions or in continuous light. Ocular melatonin was also suppressed in albinos and in dilute mutants. At midday sampling, melatonin was only half as high in albinos as in wild types. Intraocular pressure (IOP, daytime readings) was uniformly low in diurnal birds and was elevated in all quail reared under continuous light. Thus in pigmented birds, a high melatonin level was associated with high IOP, but in albinos displaying high IOP, ocular melatonin was not elevated. Lithium chloride, mixed in the feed, brought about a pronounced reduction in plasma, pineal, and ocular melatonin, in wild-type quail reared on a diurnal schedule. This confirms earlier findings in lithium-fed rats. Golden hamsters displayed a characteristic diurnal cycle of pineal melatonin, with a sharp middark peak; in albino hamsters, also kept on a diurnal schedule, this peak occurred at the same time, but albinos had melatonin levels only about one-third as high as those of pigmented animals.
采用放射免疫分析法对几种日本鹌鹑遗传品系中的褪黑素进行了测定。在夜间峰值时测量的血浆褪黑素（PM），在按照昼夜光照时间表饲养的野生型鹌鹑中最高；在持续光照下，该PM峰值受到抑制。白化鹌鹑的褪黑素水平较低，无论其是在昼夜条件下饲养还是在持续光照下饲养。白化鹌鹑和稀释突变体中的眼内褪黑素也受到抑制。在中午采样时，白化鹌鹑体内的褪黑素仅为野生型鹌鹑的一半。昼夜活动的鸟类的眼压（IOP，白天读数）一直较低，而在持续光照下饲养的所有鹌鹑的眼压都升高了。因此，在有色素的鸟类中，高褪黑素水平与高眼压相关，但在眼压高的白化鹌鹑中，眼内褪黑素并未升高。在按照昼夜时间表饲养的野生型鹌鹑中，混入饲料中的氯化锂使血浆、松果体和眼内的褪黑素显著降低。这证实了早期在喂食锂的大鼠中的发现。金黄仓鼠表现出松果体褪黑素的典型昼夜节律，在午夜有一个急剧的峰值；同样按照昼夜时间表饲养的白化仓鼠，该峰值出现在同一时间，但白化仓鼠的褪黑素水平仅为有色素动物的约三分之一。
