PUTATIVE MELATONIN RECEPTORS IN A HUMAN BIOLOGICAL CLOCK
PUTATIVE MELATONIN RECEPTORS IN A HUMAN BIOLOGICAL CLOCK
复制标题
DOI：
10.1126/science.2845576
复制
发表时间：
1988-10-07
期刊：
影响因子：
56.9
通讯作者：
STOPA, EG
中科院分区：
文献类型：
--
作者：
REPPERT, SM;WEAVER, DR;STOPA, EG
使用 125I 标记的褪黑激素进行体外放射自显影来检查人类下丘脑中褪黑激素的结合位点。特异性 125I 标记的褪黑激素结合位于视交叉上核，即假定的生物钟部位，在其他下丘脑区域不明显。在成人和胎儿的下丘脑视交叉上核中一致发现了特异性 125I 标记的褪黑激素结合。不同浓度褪黑激素的竞争实验的光密度分析显示单相竞争曲线，成人（150皮摩尔）和胎儿（110皮摩尔）的视交叉上核具有可比较的半最大抑制值。微摩尔浓度的褪黑激素激动剂 6-氯褪黑激素完全抑制特异性 125I 标记的褪黑激素结合，而相同浓度的血清素和去甲肾上腺素仅导致特异性结合的部分减少。结果表明，假定的褪黑激素受体位于人类生物钟中。
In vitro autoradiography with 125I-labeled melatonin was used to examine melatonin binding sites in human hypothalamus. Specific 125I-labeled melatonin binding was localized to the suprachiasmatic nuclei, the site of a putative biological clock, and was not apparent in other hypothalamic regions. Specific 125I-labeled melatonin binding was consistently found in the suprachiasmatic nuclei of hypothalami from adults and fetuses. Densitometric analysis of competition experiments with varying concentrations of melatonin showed monophasic competition curves, with comparable half-maximal inhibition values for the suprachiasmatic nuclei of adults (150 picomolar) and fetuses (110 picomolar). Micromolar concentrations of the melatonin agonist 6-chloromelatonin completely inhibited specific 125I-labeled melatonin binding, whereas the same concentrations of serotonin and norepiephrine caused only a partial reduction in specific binding. The results suggest that putative melatonin receptors are located in a human biological clock.