방사선 피폭에 의한 금붕어 장관 평활근의 수축활성에 관한 연구

Abstract

Radioactive ^(18)F isotope used at PET(Positron Emission Tomography) was radiated on goldfish. The change of intestine contractibility was measured by physiograph with the increase of time lapse after the exposure to the ^(18)F isotope, which was created when the concentrated oxygen water combined with hydrogen was exposed to the positron accelerated by the cyclotron. The distance between the goldfish and the ^(18)F isotope of 580 mCi was approximately 4 cm. The exposure time was 4 hours, and then the absorption level was approximately 2 Gy when the distance between the goldfish and the ^(18)F isotope, and the expose time and half decay time of the ^(18)F isotope, were considered. The neutrotransmitter was an acetylcholine of 10^(-6) mol used for observing the contractibility of isolated goldfish intestines. The buffer consisted of NaCl 110 mmol, KCl 2 mmol, 1 mmol, CaCl₂· 2H₂O 1 mmol, Glucose 10 mmol and 0.5MTris-HCl (ph7.8) 5 mmol. The control group were goldfish which were not exposed to the ^(18)F isotope. The contractibility of the control group had about a gravitational force of 0.8±0.2 g. The contractibility of the goldfish exposed to 2 Gy radiation was measured at 2 hours, 1, 2, 3, 4, 5, 6, 9, 12, 15 and 30days lapsed after the radiation. The contractibility of the 2 hour lapse was a gravitational force of 0.4±0.1 g which was approximately 50% of the control group. The contractibility of the 1day lapse was the gravitational force of 0.2±0.1g which was 25% of the control group. The contractibility of the 2 days lapse was a gravitational force of 0.5±0.2 g. The contractibility was gradually increased up to 75% of the control group with an increase of the lapse time between 2 days and 15 days. After a 36 day lapse, the contractibility was a gravitational force of 0.9±0.2 g. Therefore the contractibility of the 1 day lapse was the lowest and the contractibility was gradually increased up to 100% of the control group with an increase of the lapse time between 2 days and 36 days. It may be considered that the lowest vital activity at the 1 day lapse recovered gradually from the exposure to the ^(18)F isotope.