Fehler: Laden des Popup-Fensters fehlgeschlagen
Secretion of a Differentiated Cuticle after Apolysis in vitro in Cockroach Leg Integument
Pieces of the integument cut off from the hind tibiae of the freshly moulted adult cockroaches were cultivated in vitro. The epidermis reacted to the application of 2 x 10-5 mol l-1 ecdysterone by an apolysis. If thereafter the hormone concentration stayed above a concentration of 2 x 10-7 mol l-1 only epicuticle and exocuticle were deposited. However, when the hormone concentration was reduced below a critical threshold, that was possibly between 2x10-7 and 2x10-8 mol l-1, a composite procuticle with exocuticle and endocuticle was deposited. Neither application of dibutyryl-cAMP to the culture medium, nor co-cultivation of the ventral nerve cord of a freshly moulted adult had distinct effects. Obviously, bursicon was not necessary for deposition of the endocuticle; instead, Riddiford´s sequential cascade model was fulfilled. The cuticle also developed the typical patterns of sclerotization independently of the application of dibutyryl-cAMP and the co-cultivation of a nerve cord.