Isolation of Phospholipase A_2 Activating Peptide From Inflamed Gingival Tissues.

1990 Fiscal Year Final Research Report Summary

• Project/Area Number: 01571014
• Research Category: Grant-in-Aid for General Scientific Research (C)
• Allocation Type: Single-year Grants
• Research Field: Functional basic dentistry
• Research Institution: Osaka University, Faculty of Dentistry
• Principal Investigator: SAITO Kihachi Osaka University, Faculty of Dentistry, Pharmacology, Associate Professor, 歯学部, 助教授 (40110788)
• Co-Investigator(Kenkyū-buntansha): MAEDA Sadaaki Osaka University, Faculty of Dentistry, Pharmacology Research Assistant, 歯学部, 助手 (00135732) ; INOKI Reizo Osaka University, Faculty of Dentistry, Pharmacology Professor, 歯学部, 教授 (60028719)
• Project Period (FY): 1989 – 1990
• Keywords: Phospholipase A_2 / Peptide / Gingival tissues / Carrageenin induced granuloma

Research Abstract

It is well known that prostaglandins are intimately involved in inflammatory responses. Prostaglandins are synthesized by phospholipase A_2 (PLase A_2), a rate-limiting enzyme for their synthesis. Thus, group of drugs inhibiting PLase A_2 activity possess an anti-inflammatory action. On the contrary, we have reported the existence of PLase A_2 activation components in the extract of granuloma induced in the rat by carrageenin. The present study was initiated aiming for the demonstration of possible existence of this component in inflammatory gingival tissues.
1) Component activating PLase A_2 activity was isolated from an extract of granuloma induced in the rat by carrageenin. The isolation procedures consisted of extraction in 2 % phenol, adsorption on and desorption from charcoal, gel filtration on Sephadex G-25, G-10 and DEAE cellulose column. The material was finally isolated to homogeneity in high pressure liquid chromatography.
2) Approximate molecular weight estimation in Sephadex G-10 column gave 800. Digestion of component with leucine aminopeptidase resulted in the loss of PLase A_2 activation. These results indicated that PLase A_2 activating component is a peptide having small molecular weight.
3) Amino acid analysis of the PLase A_2 activating component gave a composition of amino acid of alanine, aspartic acid, leucine, phenylalanine and serine.
4) Trials of isolating the material from inflamed gingival tissues was unsuccessful. Another trial estimating the component in inflamed gingival tissues will be made following the production of antibody against the peptide prepared from carrageenin induced granuloma.