Hardeland R
Institut für Zoologie und Anthropologie, Universität Göttingen, Germany.
Reprod Nutr Dev. 1999 May-Jun;39(3):399-408. doi: 10.1051/rnd:19990311.
Melatonin seems to be an almost ubiquitous substance, which has been detected not only in metazoans, but also in all major non-metazoan taxa investigated, including bacteria, dinoflagellates, euglenoids, trypanosomids, fungi, rhodophyceans, pheophyceans, chlorophyceans and angiosperms. Despite its vast abundance, little is known to date about its functions. Its presence is not necessarily associated with circadian rhythmicity, which is evident in yeast. Circadian rhythms of melatonin have been reported in non-metazoans only for several unicellular organisms and in one angiosperm. In dinoflagellates, which have been studied in the most detail, the effects on enzyme activities and on phase shifting are known, but the most spectacular actions concerning the stimulation of bioluminescence, changes in cytoplasmic pH and induction of resting stages, can be related to a metabolite of melatonin, the 5-methoxytryptamine; therefore, melatonin should also be considered as a source of other agonists.
褪黑素似乎是一种几乎无处不在的物质，不仅在后生动物中被检测到，而且在所有被研究的主要非后生动物类群中也有发现，包括细菌、甲藻、裸藻、锥虫、真菌、红藻、褐藻、绿藻和被子植物。尽管其含量丰富，但迄今为止对其功能却知之甚少。它的存在不一定与昼夜节律相关，这在酵母中很明显。仅在几种单细胞生物和一种被子植物中报道了非后生动物中褪黑素的昼夜节律。在研究最为详细的甲藻中，已知其对酶活性和相位转移的影响，但与生物发光刺激、细胞质pH值变化和静止期诱导相关的最显著作用可能与褪黑素的一种代谢产物5-甲氧基色胺有关；因此，褪黑素也应被视为其他激动剂的来源。
