Over stimulation on the mucous membrane of the nasal septum was reported to bring histopat hological changes of vascular system of distant organs. Authors investigated the difference of these histopathological changes on the distant organs between two groups, one was adult rabbits and the other was young rabbits. The stimuli given were submucosal injection to the nasal septum, with 0.85% saline and 0.1% pilocarpine hydrochloride. The following results were obtained : 1) More conspicious histopathological changes were seen in most organs in adult rabbits. 2) There was no difference of histopathological changes according to different stimulating drugs in the lung. 3) There was no difference of histopathological changes according to different stimulating drugs in the kidney of young rabbits, but it was remarkable in changes in adult rabbits. 4) There were more remarkable histopathological changes in the liver of pilocarpine injected adult rabbits. 5) There were a little changes in the adrenal gland and testis in all cases.