Ultrastructural and physiological studies on the function of pituitary intermediate lobe in mice.

小鼠垂体中叶功能的超微结构和生理学研究。

基本信息

批准号：
62540568
负责人：
KOBAYASHI Yasuo
金额：
$ 1.28万
依托单位：
Okayama University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1987
资助国家：
日本
起止时间：
1987 至 1989
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-62540568/
关键词：
Mouse Pituitary intermediate lobe Electron microscope Morphometry Polydipsia-polyurea Urea 浸透圧多飲

项目摘要

The present studies demonstrated a new fact that oral urea administration resulted in hypersecretion of pituitary intermediate lobe(PIL) cells in mice. Oral urea is the third factor, besides our previous studies of dietary Na-deficiency (1974,1976) wid of experimental polydipsia (1984), that stimulates PIL cells in fine structure. The outline of the ultrastructural and morphometric studies is described as follows:(1) Alterations in PIL cells of suckling mice fed a liquid diet supplemented with 1% urea. Suckling dams (day 12-17 of lactation) were fed with either a liquid diet (11.5% powdered milk) or the liquid diet containing 1% urea. Morphometric study resulted in the hypersecretion in PIL cells of dams being given the urea-containing liquid diet more significantly than that of the liquid diet control.(2) Alterations in PIL cells of male mice fed a liquid diet supplemented with 1% urea. Young adult male mice were fed with the liquid diet containing 1% urea for 10 days in order to ascertain whether oral urea could stimulate PIL cells not only in lactating dams but also in male mice. The morphometric analysis showed the result that oral urea stimulated significantly the secretory activity of PIL cells in male mice.(3) Alerations in PIL cells of male mice given the pelleted food containing urea in the concentration of 6%, 12% and 24% for 14 days. Morphometric result revealed the increment of segretion activity in PIL cells of mice given urea- containing pellets in a dose dependent manner. Water consumption also increased in parallel to the urea concentrations adopted. These results are interpreted that oral urea stimulation of PIL cells is through a mechanism of either (1)attenuation of hypothalamic inhibitory control over PIL cells or (2)an involvement of PI hormones in the excretion of excess urea, or (3) hyponatremia caused by high blood urea concentration.

目前的研究证明了一个新事实，即口服尿素导致小鼠垂体中间叶（PIL）细胞分泌过多。除了我们之前对膳食钠缺乏（1974，1976）和实验性烦渴（1984）的研究之外，口服尿素是第三个因素，它刺激PIL细胞的精细结构。超微结构和形态测量研究的概要如下：(1)添加1%尿素流质饲料喂养的乳鼠PIL细胞的变化。乳母（哺乳期第 12-17 天）饲喂流质饲料（11.5% 奶粉）或含 1% 尿素的流质饲料。形态计量学研究表明，给予含尿素流质饲料的母鼠PIL细胞分泌过多的现象比流质饲料对照更显着。(2)添加1%尿素的流质饲料喂养的雄性小鼠PIL细胞的变化。给年轻的成年雄性小鼠喂食含有1%尿素的流质饲料10天，以确定口服尿素是否不仅可以刺激哺乳期母鼠，而且可以刺激雄性小鼠的PIL细胞。形态计量学分析结果显示，口服尿素显着刺激雄性小鼠PIL细胞的分泌活性。(3)给予6%、12%和24%尿素颗粒食品后雄性小鼠PIL细胞的变化。 14天。形态测定结果显示，以剂量依赖性方式给予含尿素颗粒的小鼠的 PIL 细胞中的分离活性增加。用水量也随着尿素浓度的增加而增加。这些结果被解释为口服尿素对 PIL 细胞的刺激是通过以下机制实现的：(1) 下丘脑对 PIL 细胞的抑制控制减弱，或 (2) PI 激素参与过量尿素的排泄，或 (3) 引起的低钠血症由于血尿素浓度高。