Learning Objectives:
Understand the role of mast cells in enhancing innate resistance to the toxic effects of certain reptile and arthropod venoms through the release of proteases that can degrade toxic components of the venoms.

Understand the role of mast cells in reducing the toxicity of high levels of endogenous peptides, such as endothelin-1 and VIP, which can induce mast cell degranulation and thereby cause the mast cell to release proteases that then can degrade the peptides.