Matsuda Kouhei, Shimakura Sei-Ichi, Maruyama Keisuke, Miura Tohru, Uchiyama Minoru, Kawauchi Hiroshi, Shioda Seiji, Takahashi Akiyoshi
Laboratory of Regulatory Biology, Graduate School of Science and Engineering, University of Toyama, 3190-Gofuku, Toyama 930-8555, Japan.
Neurosci Lett. 2006 May 22;399(3):259-63. doi: 10.1016/j.neulet.2006.02.005. Epub 2006 Feb 28.
Melanin-concentrating hormone (MCH) is a hypothalamo-pituitary peptide, which was first identified in the salmon pituitary as a hormone affecting body color. Recently, MCH has been implicated in the regulation of feeding behavior and energy homeostasis in mammals. Despite a growing body of knowledge concerning MCH in mammals, however, there is little information about the effect of MCH on appetite and behavior in fish. The aim of the present study was to investigate the action of MCH on feeding behavior and spontaneous locomotor activity in the goldfish. We administered synthetic MCH by intracerebroventricular (ICV) injection and examined its effect on food intake and locomotor activity using an automatic monitoring system. Both types of synthetic MCH we employed, which are of fish and human origin, were effective in stimulating aggregation of melanin granules in the melanophores of goldfish scales. Cumulative food intake was significantly decreased by ICV injection of both MCHs in a dose-dependent manner. ICV injection of fish MCH at the same doses as those used for examination of food intake induced no marked changes in locomotor activity during the observation period. These results suggest that MCH influences feeding behavior, but not spontaneous locomotor activity, in the goldfish, and may exert an anorexigenic action in the goldfish brain, unlike its orexigenic action in mammals.
黑色素浓缩激素（MCH）是一种下丘脑 - 垂体肽，最初在鲑鱼垂体中被鉴定为一种影响体色的激素。最近，MCH被认为参与了哺乳动物的摄食行为和能量稳态调节。然而，尽管关于哺乳动物MCH的知识越来越多，但关于MCH对鱼类食欲和行为影响的信息却很少。本研究的目的是调查MCH对金鱼摄食行为和自发运动活动的作用。我们通过脑室内（ICV）注射给予合成MCH，并使用自动监测系统检查其对食物摄入量和运动活动的影响。我们使用的两种合成MCH，分别来源于鱼类和人类，均能有效刺激金鱼鳞片黑素细胞中黑色素颗粒的聚集。脑室内注射两种MCH均以剂量依赖性方式显著降低累积食物摄入量。以与检查食物摄入量相同的剂量脑室内注射鱼类MCH，在观察期内对运动活动未引起明显变化。这些结果表明，MCH影响金鱼的摄食行为，但不影响其自发运动活动，并且可能在金鱼脑中发挥厌食作用，这与其在哺乳动物中的促食欲作用不同。
