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

A Role of Pancreatic-type Phospholipase A2 in Gastric Acid Secretion

胰型磷脂酶A2在胃酸分泌中的作用

基本信息

批准号：
01580162
负责人：
TOJO Hiromasa
金额：
$ 1.34万
依托单位：
Osaka University Medical School
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (C)
财政年份：
1989
资助国家：
日本
起止时间：
1989 至 1990
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-01580162/
关键词：
Pancreatic phospholipase Group II Phospholipase A2 Chief Cell parietal Cell Phospholipid Metabolism 消化管胃酸分泌

项目摘要

1. A phospholipase A2 (PLA2) was purified from rat gastric mucosa and its NH-2-terminal amino acid sequence, peptide maps obtained on lysylendopeptidase digestion, and immunochemical properties were identical to those of rat pancreatic PLA2. The nucleotide sequence of gastric PLA2 cDNA was completely identical to that of pancreatic PLA2 cDNA.2. A PLA2 was solubilized from the membrane fractions with 1% Triton X-100 and then purified to homogeneity. Its NH2-terminal amino acid sequence and immunochemical propertries were identical to those of pancreatic type PLA2 in the supernatant fraction.3. RNA blot analysis showed that group II PLA2 transcript existed in rat gastric mucosa. The expression level of group II PLA2 protein was, however, very low.4. We have developed an Enzyme Immuno-assay (EIA) system for pancreatic PLA2.5. The contents of pancreatic PLA2 in isolated chief cells and parietal cells were determined by EIA and enzyme activity measurement. Pancreatic-type PLA2 was mainly present in the chief cell fractions and parietal cells contained a small, but significant amount of pancreatic PLA2. Immunoelectron microscopic observation showed that pancreatic PLA2 not only existed in the zymogen granules in chief cells but also in the intracellular canaliculi in parietal cells.6. Pancreatic PLA2 was Secreted from Gastric Chief Cells on Stimulation by Carbachol.7. These results suggested that pancreatic PLA2 in gastric mucosa may play a role in digestion of phospholipids in foods and in the apical membrane turnover of parietal cells.8. The nucleotide sequence of group II PLA2 cDNA from rat spleen was determined. Group II PLA2 was preferentially present in the mononuclear phagocytic cells in rat spleen and liver.

1.磷脂酶A2（PLA 2）纯化大鼠胃粘膜和其NH-2-末端氨基酸序列，赖氨酸内肽酶消化获得的肽图，和免疫化学性质是相同的大鼠胰腺PLA 2。胃PLA 2 cDNA的核苷酸序列与胰腺PLA 2 cDNA的核苷酸序列完全相同.用1%Triton X-100从膜级分中溶解PLA 2，然后纯化至均匀。其氨基端氨基酸序列和免疫化学性质与上清中的胰腺型PLA 2相同. RNA印迹分析表明，大鼠胃粘膜中存在Ⅱ型PLA 2转录本。而Ⅱ型PLA 2蛋白的表达水平很低.我们已经开发了一种酶免疫分析（EIA）系统的胰腺PLA2.5。采用酶免疫分析法和酶活性测定法测定主细胞和壁细胞中磷脂酶A2的含量。胰腺型磷脂酶A2主要存在于主细胞组分和壁细胞含有少量，但显着量的胰腺磷脂酶A2。免疫电镜观察显示，胰腺PLA 2不仅存在于主细胞的酶原颗粒中，而且存在于壁细胞的胞内小管中.胃主细胞在卡巴胆碱刺激下分泌胰腺PLA 2.这些结果表明，胃粘膜中的胰腺PLA 2可能在食物中磷脂的消化和壁细胞顶膜更新中发挥作用.测定了大鼠脾Ⅱ型磷脂酶A2 cDNA的核苷酸序列。Ⅱ组PLA 2优先存在于大鼠脾脏和肝脏的单核吞噬细胞中。