It is well known that the most frequent symptom of radiotoxemia is concerned with the digestive system and that the symptom does not accompany any histological changes unless an extremely large dose is given. KUSUMOTO proved that the secretory activity of the gastric peptic cells of rats was lowered positively after the irradiation of 500r on the epigastrium and on the hypogastrium-thighs region regardless of the area of the irradiation, and that the secretion of the histamine-like hormone productin. (FUJIE) from the gastric surface cells which promotes the secretory activity of the peptic cells was not lowered to any remarkable degree. He further injected action of the discharged productin was inhibited by a certain substance which might be produced in the tissue irradiated.The secretory activity of the pancreatic cells, especially the production of zymogen granules, is said to be promoted by the productin as well (FUJIE). The author attempted to study the effects of the X-ray irradiation on the pancreatic cells so that the action of the X-ray irradiation on the productin behaviour might be made clearer.
I. Materialsand Methods.Adult and male albino rats accustomed to a regular feeding of Mc COLLUM's artificial diet were used, and all the animals were unfed for 24 hrs. before the experiment. Series A. Control. An artificial diet was given. Samples were taken before and at periods of 1/2, 1, 2, 3, 6hrs. after the diet.Series B. For the study on the effects of X-ray irradiation.1. A single dose 500r was given on the epigastrium, an hour later the diet was given. Samples were taken at the same periods as in the controls.2. A daily dose 100r was given on the epigastrium for 5 days before every feeding. Samples were taken before and after the last diet at the same periods as above.3. A single dose 500r was given on the hypogastrium and the thigh, an hour later the diet was given.4. A daily dose 100r was given for 5 days on the hypogastrium-thighs region, an hour later the diet was given. X-ray injuries. 1.. Prior to the irradiation of 500r on the epigastrium and to the diet, Pereston-N (polyvinylpyrrolidon) 10cc/kg weight was injected into the abdominal cavity. Viz. 5min. after the injection, X-ray was irradiated and, an hour after the irradiation, the diet was given. Samples were taken before and at periods of 1/2, 1, 2, 3, 6hrs. after the diet.2. Thioctic acid 12.5mg/kg weight was injected into the abdominal cavity prior to the administration of X-ray and the diet.3. 5-oxy-anthranilic acid 10mg/kg weight and 100mg/kg was injected into the abdominal cavity before the irradiation and the diet.Throughout these experiments, the X-ray irradiation was conditioned as follows: Tube voltage 180KVp, tube current 15mA, filter 1.0mm Cu and 1.5mm Al, focal skin distance 400mm and rate dose 52.9r/min. During the irradiation, the animals were laid on their backs and enclosed in a 3mm thick leaden cover with a hole of gastrium and the thigh.To take samples, the thorax was opened under deep ether narcosis and LUNA's liquid was inj...