Abstract
Recently, Hayashi of our Department has completed enzymatic studies on the content of the obstructed intestinal tract. The author attempted pharmacological studies on the obstructed intestinal tract itself, which is presumed to be the supply source of the content in order to provide a key to solve the problem relative to the mechanism of the manifestation of the intoxication symptoms of the acute ileus. Further, the actions of the content of the obstructed intestinal tract on the excised intestinal tract, especially the presence of absence of a substance demonstrating a histamin-like action in it, were investigated. The author's method to establish an experimental ileus was to make an obstructed intestinal tract by cutting off a portion of the small intestine or the duodenum and to make an anastomosis of the cut ends of the intestine, instead of a simple ligature. By doing as the above, the author also performed experiments to investigate the sensitiveness to various chemical agents of the excised intestinal tracts from the upper and lower portions of the anastomosed intestine after an elapse of a fixed period of time the operation.. The followings are the conclusions drawn from the experiments.
1) when the obstruction was established in the lower portion of the small intestine by the author's technique, most of the rabbits became fatal after the elapse of 60 hours. In the case of the obstruction in the duodenum, more fatal cases were observed, , therefore, the observation was restricted within 15-18 hours from the operation.
2) The voluntary movement of the obstructed intestinal tract in the small intestine was very weak and irregular. This tendency became more and more intense as the time elapses. The sensitiveness of the intestinal tract to pilocarpine, acetylcholine, vagostigmin, , atropine, adrenaline, barium etc, was found to remarkably lower than the normal.
3) In the case of obstructed intestinal tract in the duodenal portion (non-ligatured and ligatured pancreatic ducts are included), almost no voluntary movement was noted after the elapse of 18 hours. The sensitiveness to the above various chemical agents was also definitely lower compared with the control.
4) In the case of obstructed intestinal tract in the duodenal portion (non-ligatured and ligatured bile duct are included), almost no voluntary movement was noted as it was in the case of 3) . Its sensitiveness to various chemical agents was found clearly lower than the normal. The sensitiveness to various chemical agents other than adrenaline was found slightly more sensitive in the obstructed intestinal tract including ligatured bile duct.
5) The reaction of the excised intestine from the upper part of the anastomosis in the lower part of the small intestine to adrenaline was found lower than the normal. The reaction to acetylcholine was found sometime strong and sometime weak according to its concentration after 24 hours from the operation. The intestinal tract which reacted to acetylcholine strongly reacted to vagostigmin also strongly.
6) Generally, the excised intestine from the lower part of the anastomosis in the lower part of the small intestine was found less sensitive to various chemical agents, and this tendency became more and more remarkable as the time elapses.
7) Atropine, adrenaline, acetylcholine and barium acted upon the excised intestine from the upper part of the anastomosis in the duodenum similarly to the control case in the case where it included the non-ligatured pancreatic duct, but acted only weakly in the case when it included ligatured pancreatic duct. The action of pilocarpine or acetylcholine to the excised intestine in the case when it included non-ligatured bile duct was stronger than control. The action of vagostigmin was never found to be stronger than the control.
8) To the excised intestine from the lower part of the anastomosis in the duodenum only acetylcholine acted stronger
