权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Study on molecular mechanism of melanocyte-stimulating hormone system in the chicken

鸡促黑素细胞激素系统的分子机制研究

基本信息

批准号：
12640650
负责人：
TAKEUCHI Sakae
金额：
$ 2.3万
依托单位：
OKAYAMA UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

项目摘要

1. The presence and possible physiological roles of a-MSH in the peripheral tissues of birds have not established. By a combination of RT-PCR, immunocytochemitry and in situ hybridization, we identified the expression of a-MSH in the eye, which is regulated temporally and spatially in the developing chicken. The data clearly indicated that the retinal pigment epithelial cells (RPE cells) and the cone cells are intraocular sources of a-MSH in the embryonic and postnatal life of the chicken, respectively. Embryonic expression of a-MSH in the RPE cells implies a possible role for the peptide in ocular development This is the first report demonstrating the expression of a-MSH in peripheral tissues in birds, and supports our hypothesis that avian a-MSH is a paracrine/autocrine hormone.2. Growth hormone (GH) is considered to play a role in the phatogenesis of diabetic retinopathy. RT-PCR and 5'RACE analysis identified a novel GH isoform expressed in the developing chicken eye. Immunocytochemistry revealed that the binding of the novel GH isoform, named as s-cGH, to GH receptors in the RPE cells is temporally regulated and correlates well with the production of a-MSH in the RPE cells during embryonic development, implying a possible involvement of s-CGH in the regulation of ocular development.3. The neural mechanisms involved in the compensatory hyperphagia exhibited by many vertebrate species after a fast are not fully understood but, in mammals, appear to involve neutritionally-sensitive neurons that co-express neuropeptide Y (NPY) and agouti-related protein (AGRP) in the infundibular hypothalamus. We investigated whether these neurons have been evolutionarily conserved in a non-mammalian vertebrate, the Japanese quail. Double-label in situ hybridization revealed that majority of NPY neurons in the infundibular nucleus co-express AGRP mRNA, indicating that this cell type has been neuroanatomically and functionally conserved during vertebrate evolution. .

1.α-MSH在鸟类外周组织中的存在和可能的生理作用尚未确定。通过RT-PCR、免疫细胞化学和原位杂交相结合的方法，我们鉴定了α-MSH在鸡眼内的表达，它在发育过程中受到时间和空间的调控。这些数据清楚地表明，视网膜色素上皮细胞（RPE细胞）和视锥细胞是眼内的α-MSH在胚胎和出生后的生活，分别来源。这是第一份证明α-MSH在鸟类外周组织中表达的报告，支持了我们的假设，即鸟类α-MSH是一种旁分泌/自分泌蛋白。生长激素（GH）被认为在糖尿病视网膜病变的发生中起作用。RT-PCR和5 'RACE分析鉴定了一种新的GH异构体在发育中的鸡眼中表达。免疫细胞化学结果显示，新的GH亚型（s-CGH）与RPE细胞GH受体的结合受时间调节，并与胚胎发育过程中RPE细胞α-MSH的产生密切相关，提示s-CGH可能参与了眼发育的调控.许多脊椎动物在禁食后表现出的代偿性摄食过多的神经机制还不完全清楚，但在哺乳动物中，似乎涉及在漏斗下丘脑中共表达神经肽Y（NPY）和刺豚鼠相关蛋白（AGRP）的营养敏感神经元。我们研究了这些神经元是否在非哺乳类脊椎动物日本鹌鹑中进化保守。双标记原位杂交显示，大多数神经肽Y神经元在漏斗核共表达AGRP mRNA，表明这种细胞类型已在脊椎动物进化过程中神经解剖学和功能保守。.