Studies on mast cells of Rana tigrina

Mast cell degranulators cause vasoconstriction in the frog. A comparative study of the mesenteric mast cells of the frog and rat showed that the frog mast cells differed from those of the rat in having a dense perigastric instead of a sparse ideal distribution, and in responding to compound 48/80 by a rapid and marked disappearance and/or fragmented appearance instead of classical degranulation. The vasoconstriction and mast cell response after in vivo compound 48/80 appeared related since they showed a parallel increase when the dose was increased.