[Spectrum of acid proteases in the gastric juice of dogs in the normal state and in experimental atophan-induced stomach ulcer]. 
Study of the spectrum of acid proteases of dog gastric juice secreted in response to different stimuli in health and atophan gastric ulcer has shown that gastric juice may contain up to 17 proteases as evaluated from relative electrophoretic mobility of protease fractions.  In individually taken gastric juice samples, there occur 4-17 or mostly about 7-9 proteases, depending on the stimulus.  During ulcer formation, the incidence pattern of proteases that are secreted in response to all the stimuli noticeably deviates from normal.  However, the most demonstrable alterations occur as a result of histamine administration, manifesting in the emergence of 4 fractions undetectable in health and increased secretion of the remaining proteases.  Apparently, ulcer formation is accompanied by disturbance of the mechanisms that control the secretion of proteases of gastric juice, especially after histamine administration.