Project/Area Number |
01570130
|
Research Category |
Grant-in-Aid for General Scientific Research (C)
|
Allocation Type | Single-year Grants |
Research Field |
General medical chemistry
|
Research Institution | Osaka University |
Principal Investigator |
OKAMOTO Mitsuhiro Osaka University Medical School, Department of Molecular Physiological Chemistry, Professor, 医学部, 教授 (90028613)
|
Project Period (FY) |
1989 – 1990
|
Project Status |
Completed (Fiscal Year 1990)
|
Budget Amount *help |
¥2,100,000 (Direct Cost: ¥2,100,000)
Fiscal Year 1990: ¥600,000 (Direct Cost: ¥600,000)
Fiscal Year 1989: ¥1,500,000 (Direct Cost: ¥1,500,000)
|
Keywords | Phospholipase A_2 / Chief Cell / Paneth Cell / PCR / Kupffer Cell / Macrophage / Lipopolysaccharide / Endotoxin / I群PLA_2 / II群PLA_2 / 胃粘膜 / 腸粘膜 |
Research Abstract |
Mammalian tissues contain two distinct kinds of phospholipase A_2. The group I phospholipase A_2 is similar to a phospholipase A_2 secreted in pancreatic juice, while the group II isozyme is structurally similar to a phospholipase A_2 contained in viperine (snake) venom. This study was undertaken to identify the isozymic type of phospholipase A_2 contained in digestive organs including stomach, small intestine, large intestine and liver. Following results were obtained. 1. Northern blot analysis on rat gastric mucosa mRNA was performed by using a rat group I phospholipase A_2 cDNA as a probe. The result showed that the group I enzyme is expressed in the gastric mucosa. A cDNA encoding the group I isozyme was cloned, and its nucleotide sequence was determined. The sequence is identical to that of rat pancreatic phospholipase A_2. 2. A cDNA encoding rat group II phospholipase A_2 was cloned by using PCR method, and its nucleotide sequence was determined. The group II isozyme exists in tissue of small intestine. 3. Localization of the two isozymes in the rat digestive organs was immunochemically studied. The group I enzyme exists in chief cells of gastric mucosa. The group II enzyme exists in Paneth cells of ileum, Kupffer cells of liver and monocytes/macrophages of spleen. 4. Treatment of rat with BCG and lipopolysaccharide was found to induce the group II isozyme in liver tissue. This result indicates that the group II isozyme is somehow invovlved in pathogenesis of inflammation induced by inflammatory mediators such as BCG and lipopolysaccharide.
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