Proteolytic enzyme activities in rat peritoneal exudate.

Area of Science:

• Biochemistry
• Immunology
• Cell Biology

Background:

• Peritoneal cells play a crucial role in inflammatory processes.
• Understanding the kinetics of proteolytic enzyme release is key to deciphering inflammatory mechanisms.

Purpose of the Study:

• To measure and correlate proteinase activities in rat peritoneal cells and lavage fluid with cell type distribution during inflammation.
• To investigate the temporal patterns of specific enzyme activities.

Main Methods:

• Enzyme assays using specific substrates for cathepsin G/chymase, elastase, cathepsin B, cathepsin D, and alanine-aminopeptidase (AAP).
• Analysis of peritoneal cells and cell-free supernatant (lavage fluid) over a 192-hour period.
• Correlation of enzyme activities with the quantitative distribution of peritoneal cell types.

Main Results:

• Supernatant proteinase activities peaked at 72 hours.
• Intracellular chymase and AAP activities were high initially but decreased, then rose by 24 hours.
• Cathepsin B and AAP activities remained high at 96 hours.

Conclusions:

• Intracellular activation and secretion of proteolytic enzymes can be monitored using enzyme-specific substrates.
• This approach allows tracking of peritoneal cell involvement in acute and chronic inflammation.
• Enzyme activity measurements provide a dynamic view of inflammatory cell responses.