Alpha-thrombin and trypsin use different receptors to stimulate arachidonic acid metabolism

Prostaglandins. 1994 Jun;47(6):437-49. doi: 10.1016/0090-6980(94)90044-2.

Abstract

Rat liver cells (the C-9 cell line) are stimulated to metabolize arachidonic acid by alpha-thrombin, its receptor polypeptide, gamma-thrombin, and trypsin. Prostaglandin (PG) I2 synthesis stimulated by alpha-thrombin is inhibited by dansylarginine N-(3-ethyl-1,5-pentanediyl) amide (DAPA), by hirudin, by the synthetic tyrosine-sulfated dodecapeptide corresponding to residues 53-64 of hirudin (hirugen), by the Tyr(SO3H)63-hirudin fragment 54-65 and by rabbit lung thrombomodulin. Stimulation of arachidonic acid metabolism by the receptor octapeptide, SFLLRNPN, is not affected by DAPA or hirudin. gamma-Thrombin stimulates arachidonic acid metabolism but at 300 to 400-fold higher concentrations. Trypsin stimulates arachidonic acid metabolism. Trypsin's proteolytic activity is required--its ability to stimulate is abolished if it is incubated with Na-p-tosyl-L-lysine chloromethyl ketone (TLCK) or bovine pancreatic trypsin inhibitor. Prior treatment of the rat liver cells with alpha-thrombin blocks subsequent stimulation by alpha-thrombin, but not by trypsin, whereas prior treatment with trypsin blocks subsequent stimulation by trypsin, but not the activity stimulated by alpha-thrombin. Prior treatment of the cells with the serine-proteases, chymotrypsin, pancreatic or neutrophil elastase and thrombocytin from Bothrups atrox venom, block alpha-thrombin's activation of PGI2 production, but not the activity stimulated by trypsin. These findings indicate that alpha-thrombin and trypsin stimulate PGI2 production via different receptors.

Publication types

  • Comparative Study

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Arginine / analogs & derivatives
  • Arginine / pharmacology
  • Cells, Cultured
  • Dansyl Compounds / pharmacology
  • Epoprostenol / metabolism*
  • Hirudins / analogs & derivatives
  • Hirudins / pharmacology
  • Liver / drug effects
  • Liver / metabolism*
  • Molecular Sequence Data
  • Peptide Fragments / pharmacology
  • Rats
  • Receptor, PAR-2
  • Receptors, Cell Surface / classification
  • Receptors, Cell Surface / metabolism*
  • Receptors, Thrombin / metabolism
  • Thrombin / metabolism*
  • Thrombomodulin / metabolism
  • Trypsin / metabolism*

Substances

  • Dansyl Compounds
  • Hirudins
  • Peptide Fragments
  • Receptor, PAR-2
  • Receptors, Cell Surface
  • Receptors, Thrombin
  • Thrombomodulin
  • hirugen
  • dansylarginine N-(3-ethyl-1,5-pentanediyl)amide
  • Arginine
  • Epoprostenol
  • Trypsin
  • Thrombin