Intradermal mast-cell secretion causing cutaneous mitogenesis.

This study demonstrated that mast-cell secretion elicited by intradermal injection of compound 48/80 initiated cell proliferation in rat skin. The mast-cell secretion was confirmed by microscopical demonstration of degranulation of mast cells, and by quantifying histamine release, whereas the proliferation was assessed by measuring DNA-synthesis and the frequency of mitosis. The results, which fully support our previous findings in the true mesentery, indicate that the common type of mast cell, when appropriately activated, is capable of playing a role in governing cell proliferation in diverse tissues.