The utricular function in response to acceleration of gravity was electro- physiologically studied by using tilting stimuli. A capillary ultramicroelectrode was inserted into the utricular macula vertically from its bottom of the cat, and a tilting board was rotated around the bitemporal axis of the preparations, and the board was propped in the same position for approximately 30 seconds.
The results were as follows;
1) Spontaneous discharges were recorded from 28 units in the utricular macula of the cat, and their discharge frequencies were increased or decreased by periodical changes of tilting.
2) In general, the remarkable increase of the discharge frequency was observed in the head positions of Pressure and Traction on and from the sensory cells of utricle, particularly in the head position of Pressure. But in the case of the Slipping position, the frequency was decreased.
3) In the head position of Slipping with the nose up or down, the discharge frequency was decreased in the same degree in both cases.
4) When the preparations were held stationary in the various head positions for about thirty seconds the discharge frequency remained for that period above or below their characteristic discharge frequency in every position. From these evidences, the following conclusions are drawn;
i) The perpendicular gravity acceleration is more effective in stimulating the utricular macula.
ii) It is supposed that the utricular macula is capable of signalling persistent deviations from the normal spatial orientation.

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The purpose of this paper is to elucidate pathophysiology of the eustachian tube in chronic suppurative otitis media. The eustachian tube has two functions first, it serves as a channel for the transmission of air from the nas, opharynx to the middle ear, second, as a pathway for drainage of the secretion and foreign body in the middle ear.
To investigate the first function of the tube, 1) the noise level during the inflation of the tube with a catheter and the pressure needed to the inflation of the tube were measured and 2) After the positive or negative pressure were experimentally added to the middle ear cavity through the external auditory canal, the changing pattern of the pressure by the deglutition was recorded according to Miller's method.
To investigate the second function of the tube, Indigocarmin-Chloromycetin test was used, i. e., after a;, drop of the Indigocarmin-Chloromycetin solution was applied into the tympanic cavity, the patient acts the swallowing repeatedly once each 30 seconds and the time till the solution flows down into the pharynx was measured.
These examinations were carried out in 80 (ear) cases of chronic otitis media, 26 male and 54 female cases which were aged 8 to 71 year-old. In all cases, the central perforation of the ear drum were observed and the tympanoplasty was indicated. Otoscopic findings and pathological changes of the mucous membrane of the middle ear cavity when the surgical procedure were compared with the results of the above mentioned examination of the tube.
The results obtained were as follows
1. The function of Eustachian tube in chronic otitis media was found to be normal in 30%-45% of all cases, while in 55%-70% cases the function was reduced.
2. The condition of Eustachian tube affects the results of tympanoplasty, i. e., the improvement of hearing and the control of the inflammatory process.
3. The function of Eustachian tube is more reduced when the aural discharge and the pathological change of the mucous membrane of the tympanum is in higher degree.
4. The air-inflation test by the catheterization is the most popular, however it is not reliable except in cases the function of the tube is completely disturbed.
5. To estimate the tubal function before the tympanoplasty, itis proper to do the examinations in the following order. The air-inflationtestby the catheterization should be first chosen, and when the air is inflated, the Indigocarmin Chloromycetin test should be followed.

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Clinical and histopathological investigations were performed on 175 cases of the laryngeal polyp in order to elucidate its etiology and development. Six larynges with the laryngeal polyp were examined out of 922 cases obtained by autopsy.
The results were as follows:
1) The laryngeal polyps are classified into three types according to their features; i. e., vocal cord polyp, vocal nodule and polypoid degeneration of the vocal cord. However, no histolgical differences were found among them.
2) The hoarseness was found in the history of many cases to occur suddenly in course of common cold or after the excessive use of the voice.
3) The polyp was most freqwmtly observed at the middle portion of the membranous vocal cord where the vibration of the vocal cord is the strongest (60.5%).
4) The vocal cord polyp was clinically classified into red and white one, the ratio of which was 3 to 1.
5) The polyp was histologically classified into 4 types; 1) fibrous, 2) oedematous, 3) hemorrhagic, 4) hyalinization. The most noticeable findings were the vascular i:changes such as vascular dilatation, hemorrhage, thrombus and hyalinization. Hemorrhage (fresh and old) was observed in 64% of all cases and hyalinization in 82%. Both of them were frequently found in the same specimen, especially in the early cases. It was suspected that the hyalinization was a degenerative change of hemorrhage. The fibrous type was mostly noticed in large and longstanding polyps. It indicates that the fibrous change of the tissue of the polyp is the final stage of histology.
6) Six larynges obtained by the autopsy were used to the examination by the large section, which revealed that all of the polyp originated at the site of stratified squamous cells epithelium of the vocal cord and the histological change was not limited only in the polyp but found in the surrounding tissue of the polyp.
From the results described above and the consideration of the physiology of the vocal cord as a “high speed vibrator”, the etiology of the laryngeal polyp was concluded to be circumscribed hemorrhage in the subepithelial layer of the vocal cord.

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Functions of the larynx, such as respiratory, deglutitory and phonatory, are extremely important for life. The laryngeal muscles have to keep working throughout the life. Although they are striated muscles, the mode of their contraction is presumed different from that of other striated muscles of more dynamic nature. Little information about the metabolism in normal and paretic laryngeal muscles. The need to know the metabolic pattern for deeper understanding of physiological aspects of the laryngeal muscles lead us to biochemical and electronmicroscopic investigations of these muscles.
Part 1. Biochemical investigation of laryngeal muscles.
Using a Warburg's respiratory manometer, oxygen consumption was measured in normal human laryngeal muscles and normal muscles of the larynx, heart, diaphragm and femur of dog. The results are summerized as follows:
1) In dog, oxygen consumption was greatest in the cardiac muscle, followed by laryngeal muscles, diaphragm and femoral muscle in descending order.
2) Among human laryngeal muscles investigated, the order of oxygen consumption was; the arytenoid>the vocalis>the posterior cricoarytenoid>the thyroarytenoid>the lateral cricoarytenoid.
3) Among laryngeal muscles studied in dog, oxygen consumption was greatest in the cricothyroid, moderate in the posterior cricoarytenoid and least in the vocalis muscle.
4) It indicates that aerobic metabolism is more dominant in the cardiac muscle which is predominantly tonic than in the femoral muscle which is predominantly clonic. It also indicates that laryngeal muscles are more tonic in their contraction than the femoral.
Oxygen consumption was determined also in denervated laryngeal muscles. It was greater in the vocalis than the posterior cricoarytenoid muscle in human, whereas it was less in the vocalis than in the posterior cricoarytenoid in dog. In any muscle. oxygen consumption was always greater on the denervated side than on the unaffected side. This suggests that denervated muscles present abnormal contraction, especially during early stage of denervation.
Part 2. Electronmicroscopic investigation of laryngeal muscles.
Human laryngeal muscles and canine laryngeal, cardiac, diaphragm and femoral muscles were studied with an electronmicroscope. The results are summerized as follows:
1) In dog, number of the mitochondria was greatest in the cardiac muscle, moderate in the laryngeal muscles and the diaphragm, and least in the femoral muscle.
2) Among the human laryngeal muscles investigated, the order of number of the mitochondria was; the arytenoid>the posterior cricoarytenoid>the vocalis>cricothyroid>lateral cricoarytenoid. No appreciable differences in number of the mitochondria were found among canine laryngeal muscles.
3) Development of sarcoplasmic reticulum was most remarkable in the femoral muscle, moderate in laryngeal muscles and least remarkable in the cardiac muscle.
4) There were no significant differences in the nucleus, sarcolemma, myofibril or Gorgi's apparatus among the muscles investigated.
5) Morphologically, character of a skeletal muscle should be referred to the mitochondria and the sarcoplasmic reticulum. In this meaning, laryngeal muscles have an intermediate character between the cardiac and femoral muscles.
After denervation, changes in electronmicroscopic structures began to develop within one week. Striated structure of the myofibril was still seen two weeks of ter denervation, and became less distinctive in three weeks, and destructed except the Z-band three months after dissection of the nerve. The mitochondria showed multiple changes after denervation. The speed of its deterioration varies considerably from one to another. Its ultramicroscopic structures could be partially seen even three months after denervation. Destruction of the sarcoplasmic reticulum started within one week of denervation and went on rapidly

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