[Mast cell heterogeneity in normal man].

Thermographic analysis of the skin of the forearm of normal men submitted to nasal instillation of 1 ml of a solution of 48/80, 1 X 10(-2), demonstrates that the skin vessels undergo local vasodilatation. Erythema and wheals sometimes appear, due to the stimulation of the dermal mast cells. Mast cells of the nasal mucosa are never stimulated by such instillation. The differences between dermal and nasal mast cell reactions are in accordance with the concept of mast cell heterogeneity.