A rapid increase in cAMP in response to 20-hydroxyecdysone in the anterior silk glands of the silkworm, Bombyx mori.
In the anterior silk glands (ASGs) of the silkworm, Bombyx mori, intracellular cAMP increases transiently to a very high level shortly after the hemolymph ecdysteroid peak in the prepupal period. In cultured ASGs obtained on the day of gut-purge, cAMP levels were increased by 20-hydroxyecdysone (20E), and this increase was enhanced by an inhibitor of phosphodiesterase, but was not affected by alpha-amanitin, indicating the 20E action may not be mediated via gene expression. The increase in cAMP occurred within 30 seconds of exposure to a physiological concentration of 20E (1 microM), and also by ponasterone A. Our findings indicate a nongenomic action of ecdysteroids in insects, which may be an additional mechanism by which this steroid hormone induces acute responses in tissues and cells.
Elmogy
Mohamed
M
Division of Life Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Japan.
Terashima
Jun
J
Iga
Masatoshi
M
Iwami
Masafumi
M
Sakurai
Sho
S
D000818:Animals; D012831:Bombyx / Q000502:physiology*; D002478:Cells, Cultured; D000242:Cyclic AMP / Q000378:metabolism*; D004441:Ecdysterone / Q000378:metabolism* / Q000494:pharmacology; D018978:Molting / Q000187:drug effects / Q000502:physiology*; D013997:Time Factors
D004441:Ecdysterone; D000242:Cyclic AMP