著者

富田 まり子

出版者

耳鼻咽喉科臨床学会

雑誌

耳鼻咽喉科臨床 (ISSN:00326313)

巻号頁・発行日

vol.80, no.10, pp.1577-1591, 1987-10-01 (Released:2011-11-04)

参考文献数

34

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The intrinsic laryngeal muscles contract in a slightly different fashion with each movement during respiration, deglutition and phonation. The present study evaluates the oxygen metabolism of each intrinsic laryngeal muscle, with two different experimental procedures:(1) Immunohistochemical distribution of myoglobin in the intrinsic laryngeal muscles, and (2) tissue oxygen pressure in the intrinsic laryngeal muscles during electrical stimulation of the laryngeal nerves.1. In the first series of experiments, the ratio of myoglobin-rich fibers accounted for 67.6% of the cricothyroid muscles, 47.4% of the posterior cricoarytenoid muscles, 33.9% of the lateral cricoarytenoid muscles, 31.6% of the thyroarytenoid muscles and 31.5% of the interarytenoid muscles.2. No definite pattern was observed in the arrangement of myoglobin-rich fibers in any of the intrinsic laryngeal muscles.3. In the posterior cricoarytenoid muscle, myoglobin-rich fibers were thicker than myoglobin-poor fibers. On the contrary, myoglobin-poor fibers were thicker in the thyroarytenoid, lateral cricoarytenoid and interarytenoid muscles. However, in the cricothyroid muscles there was no relationship between the amount of myoglobin and the diameter of the muscle fibers.4. In the second series of experiments, during stimulation of the laryngeal nerves in the cricothyroid and thyroarytenoid muscles, intramuscular tissue oxygen pressures decreased with the onset of muscle contraction. The tissue oxygen pressure dropped further at 30Hz than at 10Hz and showed an even greater decrease at 60Hz than at 30Hz.5. Tissue oxygen pressure decreased more in thyroarytenoid than in cricothyroid muscle.6. The results of the present studies indicate that for laryngeal function oxygen supply is more necessary in slow muscles, such as the cricothyroid and posterior cricoarytenoid muscles than in fast muscles, such as the thyroarytenoid, lateral cricoarytenoid and interarytenoid muscles.