期刊
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-MOLECULAR & INTEGRATIVE PHYSIOLOGY
卷 153, 期 3, 页码 297-302出版社
ELSEVIER SCIENCE INC
DOI: 10.1016/j.cbpa.2009.03.001
关键词
Endogenous melatonin rhythms; In vitro culture; Pineal organ; Solea senegalensis; Tinca tinca
资金
- MEC [AGL 2004-07984-C02-01]
- SENECA [05690/PI/07]
- MEC
This research aimed to investigate melatonin rhythms in the pineal organ of two nocturnal fish species, sole and tench, which show high sensitivity to light. Pineal organs were cultured in vitro under an LD (12 h light: 12 h dark) cycle to study the daily rhythmicity of melatonin release. In addition, the in vitro culture was performed under conditions of constant darkness (DD) to study the endogenous control of the rhythm. In the pineal organs cultured under an LD cycle, rhythmic melatonin release was evident in both species, with low values observed during the photophase (15.6 +/- 7.2 and 22.6 +/- 2.6 pg/mL for sole and tench, respectively) and high values coinciding with the scotophase (74.0 +/- 8.2 and 82.1 +/- 9.1 pg/mL, for sole and tench, respectively). Under LID, the rhythm had a period of 24 h (p<0.001) and presented similar acrophases for both species, located around 9-10 h after lights off (2 and 3 h before the end of the dark phase). When the pineal organs were cultured under DD, the results differed between the species studied. A marked circadian rhythm in melatonin release by the pineal was registered in tench, with lower values during the subjective day, i.e. the period that was previously day (6.2 +/- 1.6 pg/mL) and higher values during the subjective night, i.e. the period that was previously night (20.4 +/- 5.5 pg/mL). The rhythm had a mean tau of 24.1 h (p<0.01) and the acrophase was located around 12 h after lights off (the beginning of the subjective day), slightly later than that registered under LD conditions. In contrast, melatonin values in sole remained high during darkness (around 92.0 +/- 6.9 pg/mL) for four consecutive days, including subjective day periods. In short, these findings revealed that the rhythm of melatonin release in tench is under endogenous control by a circadian oscillator within the pineal organ, while no such pacemaker was evident in sole, which melatonin rhythm appeared to be exclusively light-driven. (C) 2009 Elsevier Inc. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据