Hormonal regulation of cuticle extensibility in newly emerged adult blowflies

Abstract

The cuticle of adult blowflies, Calliphora vicina, newly emerged from their puparial cases, is relatively inextensible. It becomes briefly more extensible at the time of air swallowing, when the body is inflated and the wings expanded. This plasticization is shown to be under the control of a blood-borne active factor which is indistinguishable from the tanning hormone, bursicon, in a number of ways. Cuticle plasticization is not, however, a consequence of the chemical events of tanning.