유충호르몬 에스테라제 (Juvenile hormone esterase : JHE)의 조절기작을 구명하기 위하여 누에나방(Bombyx mori) 종령기에 methoprene과 Precocene 2를 국소투여한 후 유충호르몬(Juvenile hormone : JH) III을 기질로 하여 JHE 활성도의 변동을 조사하였다. 종령기동안 JHE 활성도의 피이크는 2개이었으며, 첫 피이크는 종령유충 5일에, 두번째 피이크는 13.5일(용화직전)에 각각 나타났다. 양 피이크의 크기는 비슷하였다. Methoprene을 투여한 누에나방의 JHE 활성도는 처리 후 6시간부터 증가하기 시작하였고, 증가정도는 투여량에 따라 다르게 나타났다. 발육시기별 methoprene을 처리한 누에나방의 JHE 활성도는 종령유충 1일을 제외한 나머지 시기에서 증가하였고, 특히 3, 5, 7일에서 현저하게 증가되었다. 이러한 결과로 볼 때 JH는 JHE 활성도의 조절에 중요한 역할을 하는 것으로 생각된다. Precocene 2는 다량 투여에 의해 JHE 활성도가 감소되었으며, 처리 후 12시간부터 상대적 감소가 나타나기 시작하였다. 발육시기별 precocene 2를 처리한 누에나방의 JHE 활성도는 종령유충 3일과 7일에서 억제되었으며, 특히 3일에서 현저하게 나타났다.
The effects of topical treatment with methoprene and precocene 2 on juvenile hormone esterase (JHE) activity in last instar larvae of Bombyx mori were investigated using juvenile hormone (JH) III as substrate. During the last larval instar there were two peaks of JHE activity and the first peak occurred on day 5 and the second of a similar size on day 13.5 (just prior to pupation). The activity of JHE in larvae treated with methoprene was induced 6 hours after treatment and the influence was dose dependent. Treatment with methoprene increased the activity of JHE through the experiment except day 1 and the activities were markedly increased at day 3, 5, 7, therefore, it was revealed that JH played major role in regulation of JHE activity. The activity of JHE in larvae treated with precocene 2 was reduced, however, this reduction effect was observed only in high dose and after 12 hours commencing treatment. The activity of JHE in larvae after precocene 2 treatment during development was decreased in day 3 and 7, and reducing rate was remarkably observed at day 3.
