Jpn. J. Pharmacol. 82 (1), 74-77 (2000)

Characterization of ProteaseﾐActivated Receptors
in Rat Peritoneal Mast Cells

Hiroyuki Nishikawa¹, Atsufumi Kawabata^2,*, Ryotaro Kuroda², Minoru Nishida¹ and Kenzo Kawai<sup>1


1</sup>Research & Development Center, Fuso Pharmaceutical Industries Ltd., 2ﾐ3ﾐ11 Morinomiya, Jotohﾐku, Osaka 536ﾐ8523, Japan
²Department of Pathophysiology & Therapeutics, Faculty of Pharmaceutical Sciences, Kinki University,
3ﾐ4ﾐ1 Kowakae, HigashiﾐOsaka 577ﾐ8502, Japan
*To whom correspondence should be addressed.


Abstract: Activation of proteaseﾐactivated receptor (PAR)ﾐ1 or PARﾐ2 elicits inflammation most probably via mast cell degranulation in vivo. The present study aimed at characterizing PARs in rat peritoneal mast cells (PMC). Messenger RNA for PARﾐ1, but not for PARﾐ2, was detected in PMC. Thrombin, the PARﾐ1 agonist SFLLRﾐNH₂ or the PARﾐ2 agonist SLIGRLﾐNH₂ failed to induce histamine release from PMC. Surprisingly, the PARﾐ2ﾐinactive control peptide LSIGRLﾐNH₂ triggered histamine release from PMC. Thus, PARﾐ1, but not PARﾐ2, are expressed in PMC, whereas neither PARﾐ1 nor PARﾐ2 are considered to be involved in degranulation of PMC. LSIGRLﾐNH₂ does not appear to be appropriate as a control peptide for PARﾐ2 in inflammation studies.

Keywords: Proteaseﾐactivated receptor, Peritoneal mast cell (rat), Thrombin