Further Observations on the Disruption of Rat Mesentery Mast Cells Caused by Compound 48/80, Antigen‐Antibody Reaction, Lecithinase A and Decylamine

H ögberg , B. and B. U vnas . Further observations on the disruption of rat mesentery mast cells caused by compound 48/80, antigen‐antibody reaction, lecithinase A, and decylamine. The influence of pH, ionic milieu, temperature and enzyme inhibitors, on the disrupting action on rat mesentery mast cells of compound 48/80, antigen and decylamine has been investigated. A pH optimum around 7.4, the essentiality of Ca++ ions, the influence of temperature and the inhibitory action of various enzyme inhibitors, especially those blocking protein NH 2 ‐groups and SH‐groups, supported the view that compound 48/80 and antigen disrupt the mast cells by activating a lytic enzyme attached to the mast cell membrane. Decylamine, on the other hand, is a surface active agent that disrupts mast cells by a non‐enzymatic mechanism.