Abstract
The relationship between the histamine-releasing ability tested on suspensions of mast cells and the hypotensive effect tested on dogs of exudate portions collected directly from the pancreas at various time intervals during the course of experimental acute pancreatitis in dogs, has been studied. The histamine-releasing ability was strongest in the portions collected early during the ailment, as was the hypotensive effect. Heat-treatments influenced the hypotensive and the histamine-releasing effects in a similar way. Acidification to pH 3.0 or lower, followed by neutralization and dialysis, destroyed both the hypotensive and the histamine-releasing effect of the exudates. It is concluded that histamine release from mast cells may be involved in the causation of the hypotension which can be observed when pancreatic exudate is injected i.v. in healthy dogs.