Search tips
Search criteria 


Logo of jcinvestThe Journal of Clinical InvestigationCurrent IssueArchiveSubscriptionAbout the Journal
J Clin Invest. 1990 August; 86(2): 555–559.
PMCID: PMC296760

Mast cell chymase potentiates histamine-induced wheal formation in the skin of ragweed-allergic dogs.


Skin mast cells release the neutral protease chymase along with histamine during degranulation. To test the hypothesis that chymase modulates histamine-induced plasma extravasation, we measured wheal formation following intradermal injection of purified mast cell chymase and histamine into the skin of ragweed-allergic dogs. We found that chymase greatly augments histamine-induced wheal formation. The magnitude of the potentiating effect increases with increasing doses of chymase and becomes maximal approximately 30 min after administration. Injection of chymase without histamine does not evoke wheal formation. The chymase potentiation of histamine-induced skin responses is prevented completely by pretreatment with the H1-receptor antagonist pyrilamine, and is prevented by inactivation of chymase with soybean trypsin inhibitor, suggesting that both histamine and preserved catalytic activity are required for the effects of chymase. To examine the effects of histamine and chymase released in situ in further experiments, we measured wheal size following local degranulation of mast cells by intradermal injection of ragweed antigen or compound 48/80. We found that pretreatment with either soybean trypsin inhibitor or pyrilamine markedly reduces ragweed antigen- or 48/80-induced wheal formation, supporting the results obtained by injection of exogenous chymase and histamine. These findings suggest a novel and important proinflammatory role for chymase in modulating the effects of histamine on vascular permeability during mast cell activation.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (1020K), or click on a page image below to browse page by page.

Articles from The Journal of Clinical Investigation are provided here courtesy of American Society for Clinical Investigation