InVitro Activation of Prothoracic Glands from Diapause and Non-Diapause Destined SarcophagaArgyrostoma and CalliphoraVicina

Abstract

The in vitro activation of isolated prothoracic glands from Sarcophaga argyrostoma (Robineau-Desvoidy) to produce ecdysone was accomplished in a dose related manner (Figure 1) with extracts of prepupal brains, presumably containing prothoracicotropic hormone (PTTH) (Roberts et al.,1984). Ecdysone was measured according to Richard and Saunders (1986). The steroidogenic action of PTTH was mimicked by dibutyryl cAMP, and the phosphodiesterase inhibitor MIX (Figure 2), suggesting the involvement of a cyclic nucleotide mediated secondary messenger system in PTTH action (Smith et al. 1984)