Calcium-Dependent Histamine Release by Atp From Isolated Rat Mast Cells

Although there are evidences suggesting that an energy-requiring process is involved in the cellular reac tion leading to the release of histamine from mast cells (1-3) , the mechanisms of the "active" histamine re lease is not known.In an attempt to study the mechanisms of action of histamine liberators, we have tried to gain an insight into the ATPase activity of mast cells in the release of histamine, and found unexpectedly that adenosine-5'-triphosphate (ATP) itself induced morphological change of rat peritoneal mast cells , and in the presence of Ca" this was accompanied by the release of histamine .During this work we noticed a similar work by Diamant and Kruger (4), which in some respects agrees with our present results .Mast cells were isolated from the rat peritoneal washing following arabic gum density gradient centri fugation, a slight modification of Kimura's procedure (5), and suspended in a buffered isotonic saline solution containing a small quantity of bovine serum albumin, with or without Ca2+, and incubated at 37°C .The 杉