EXPERIMENTAL STUDIES ON THE FUNCTION OF SACCLE

Abstract

1)In purpose to investigate a function of the saccular otoliths, the author designed the new method injuring only saccular macule through external auditory canal and completely preserving the cochlea and the utricle.2)In the observation of the rabbits subjected to this method, disturbance in the labyrinth reflex was very slight and grossly, reduction of tonus in the limb muscles or the change in rotation of eye were not recognized.In the next plase, labyrinthine spinal reflex was studied by means of the electromyography.1)The dischage interval of simple tonic NMU on a M.occip.rect.min.in the rabbit whose saccular macule had been injured was mostly 0.1_??_0.2sec.on both side, and moreover the wave pattern, electrical potential and progress were not unusual.On the other hand in the bealthy side of the rabbit whose contralateral labyrinth had been injured, the discharge.interval was very irregular and also the frequency of the discharge on the same side was charactresticaly de creased.2)In the rabbit whose saccular macule had been destroyed, the kinetic reflex for the swing movement(50 100cm/sec2)was obviously appeared for the direction of foreward, backward, right, left, up ward and downward as in the normal rabbit.3)The linear acceleration reflex was thoroughly by a new accurate sine-curved lineal accelera which speed was changed(0.6 0.004g)in for steps by means of an exchanger.(1)The threshold of the liener acceleration reflex in the normal rabbit was below 9cm/sec2 together for the direction of foreward, backward, right, left, upward &downward.(2)The rabbit whose saccular macule had been injured did not react to the delicate lineal acceleration for right and left.Namely, the saccular macule has a vestibular function, that reacts to the lineal accerelation, perpendicular to the saccle macule.