Immunomodulation with Endogenous Hormone in a Pleuronectiform Fish, the Barfin Flounder

巴鳍比目鱼(Verasper Moseri)是环鳍目的一员，生活在寒冷的海盆地区。这种鱼在日本北部的水产养殖中很有希望。本研究旨在阐明环境因素(背景颜色)与包括免疫调节在内的生理状态之间的关系。作为第一步，我们通过克隆确定了原阿片黑素皮质素(POMC)的一级结构，它是几种负责免疫调节和身体颜色变化的多肽激素的共同前体。逆转录-聚合酶链式反应和Southern印迹分析相结合的结果表明，脑垂体是表达POMC-A和POMC-B基因的主要组织。结果表明，POMC-C基因在所有组织中均有表达，通过免疫细胞化学和原位杂交技术，在远侧部和中间部均可检测到POMC-C基因的产生细胞。用bl…在水族箱中放养巴氏比目鱼ACK背景越多，POMC-A、-B和-C基因的表达越高。黑鱼皮肤中POMC-C基因的表达高于白鱼。这些结果表明，背景颜色调节了POMC在脑垂体和皮肤中的表达。因此，体色的变化除了内分泌控制外，还受旁分泌或自分泌系统的控制，与黑色背景的鱼缸相比，白色背景的鱼体生长更快。黑色素浓缩激素(MCH)被认为是一种食欲增加的激素，在白鱼和禁食鱼的大脑中表达增强。根据该序列合成的POMC相关多肽对牙鲨白细胞的影响也被检测。然而，没有获得重复性。较少

Barfin flounder, Verasper moseri, is a member of Pleuronectiformes, inhabiting cold sea basin areas. This fish is promising for aquaculture in northern Japan. The present study was undertaken to clarify the relationship between an environmental factor (background color) and the physiological status, including immunomodulation. Of the barfin flounder.As a first step, we determined the primary structure of proopiomelanocortin (POMC), which is a common precursor of several peptide hormones responsible for immunomoduation and body color change, by cDNA cloning. A combination of reverse transcription-polymerase chain reaction and Southern blot analysis showed that the pituitary gland was the major tissue expressing POMC-A and -B genes. The expression of POMC-C gene was observed in all tissues examined In the pituitary, POMC-producing cells were identified in both pars distalis and pars intermedia by immunocytochemistry and in situ hybridization.Rearing of barfin flounder in a tank with a bl … More ack background resulted in higher expression of POMC-A, -B, and -C genes than those with a white background. The expression of POMC-C gene in the skin was higher in the black-reared fish than white-reared fish. These results indicate that background color modulates POMC expression in the pituitary and skin. Thus, body color change of barfin flounder is under the control of paracrine or autocrine systems in addition to endocrine control.Rearing of barfin flounder with a white background resulted in greater somatic growth than those in the black background tank. The expression of melanin-concentrating hormone (MCH), which has been identified as an appetite increasing hormone, was enhanced in the brain of white-reared fish and in fasted fish. Increased MCH in the brain of white background might have augmented the food intake.The effects of POMC-related peptides, which were synthesized based on the cDNA sequence, on barfin flounder leukocytes were also examined. No reproducibility was, however, obtained. Less