1983 年 29 巻 1 号 p. 70-94
The pathogenesis of dysphonias induced by androgenic hormones is not clearly understood even now. In this experiment, studies on a same material were performed not only phoniatrically but also histopathologically at the same time in order to shed new light on the pathogenesis. 24-hour-old female chickens were injected with androgen regularly to bring about a condition of dysphonias. After checking to be sure it was present, the ordinary sounds they produced were analyzed phoniatrically, while the lateral syringeal membrane (L. S. M.) and the medial syringeal membrane (M. S. M.) were examined histopathologically. The results were as follows; 1) Not only irregular shapes and amplitudes of the waves, but also a lowering of the fundamental frequency were observed on the oscillogram, while a lowering of the central frequency and a widening of the frequency ranges were observed on the spectrumgram. 2) When viewed under a light microscope, both the L. S. M. and the M. S. M. showed that in the lamina propria mucosa (L. P. M.), collagen fibers were running irregularly with an increase in the number of capillaries. 3) Under examination by an electron microscope, irregularly running collagen fibers as well as an increase in the number of the capillaries could be observed in the L. P. M. of the L. S. M. and the M. S. M. Finally, it was concluded that the phoniatric changes in the voices of chickens were caused by the material changes in the syringeal membranes which were the vibratory ones.