著者

花岡 利昌

出版者

社団法人日本動物学会

雑誌

動物学雑誌 (ISSN:00445118)

巻号頁・発行日

vol.59, no.9, pp.1-6, 1950-09

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In 1933, Jores found that the melanophore-hormone has some effects to shorten the time course of dark adaptaion to 11 minutes in average by collyrium of the hormone, but soon after Buschke (1934, '35) reexamined and denied it. Since then no one has attempted to investigate these effects systematically. The auther had thorough experiments about the effect of the hormone upon the scotopic adaptation of human eyes by the injection in those years since 1943. The results are shown below briefly: Preparatfon of the hormone. It is necessery for injection to preparate hormone extremely purely and the auther obtained it by the improved Stehle's method described in Table 1. The hormone contains 200 international units perccm and is injected subcutaneously. Results: (1) Effect on the scotopic adaptation. As shown in Fig. 1, it takes effects in 30 minutes after injection and attains the maximum in 2 or 3 hours and maintains the effect for 8 hours or more. The effect appears not only in the shortening the adaptation time to one third or less but also in raising the light sensibility, and after about 3 hours; the threshold value of light sensibility falls to 0.0067 micro-lux while that of the control is 6.1 micro-lux (See Table 3). (2) Effect on the visual perceptive power under low luminosity. Under extreme low illumination of 2 to 0.001 lux, the visual perceptive power was examined with Landolt's figures. Fig. 2 shows the average results of several experiments. (3) Effect on the electric 'Phosphen'. Placing the electrodes between the eyes and on the occipital region of the head and when the low voltage alternating current of 10 to 20 cycles per second is through them, one can have the luminous sense fickering in the same frequency of the current. This phenomenon of the electric 'phosphen' is arisen in a definite current by individual and is about 50 to 60 micro-amperes usually. The threshold value of this current is distinctly diminished by the injection of the hormone and reaches even to the half of the control. Though the mechanism of this phenomenon is not clear, it is interest from the viewpoint of visual physiolgy.