6533b7d9fe1ef96bd126cea6

RESEARCH PRODUCT

Ultrastructural changes of the oenocytes of Gryllus bimaculatus DEG (Saltatoria, Insecta) during the moulting cycle

subject

description

1. The oenocytes of Gryllus bimaculatus are characterized by an abundant smooth-surfaced ER (ATER). In spite of the great cell size the plasma membrane never shows extensive infoldings during the moulting cycle. In addition to mitochondria there are very large numbers of microbodies containing peroxidase but apparently not uricase. Within the second part of the instar the microbodies lie along the clefts which run through the whole cell. 2. The following changes are observed in the course of a moulting cycle: Immediately after hatching the ATER is scarcely developed, some liposomes are located within areas of ATER disappearing some hours later. 20 hours after emergence glycogen deposits appear in two forms: large deposits reaching some μm in diameter, and in distinct rosettes dispersed between the tubules of the ATER. 30 hours post-moult profiles of RER appear, which disappear together with the large glycogen deposits one day later. At the same time ATER is increased and the clefts develop within areas of elongate granules smaller than ribosomes. The number of such clefts subsequently becomes reduced probably as a result of confluence. Towards the end of the moulting cycle numerous autophagosomes appear. These digest parts of the agranular reticulum, many microbodies, and to a lesser extent, mitochondria. Residual bodies are extruded during moult whereas the clefts remain. 3. The ultrastructural features parallel those of steroid-producing cells in vertebrates. Besides this it is possible that oenocytes also engage in detoxication processes as shown for vertebrate liver.