ISSN:
1432-0878
Keywords:
Corpus allatum
;
Calliphora erythrocephala
;
Ultrastructure
;
Hormone Production
;
Release
Source:
Springer Online Journal Archives 1860-2000
Topics:
Biology
,
Medicine
Notes:
Summary An electron microscopical study of the corpus allatum (CA) of the adult female Calliphora was undertaken. The cells have a very irregular shape. Light and dark cells are found. Mitochondria occur in great numbers. Microtubules are frequently observed. Free ribosomes are plenty, but rough-surfaced reticulum is scarce. Golgi complexes are not very conspicuous. Axons, mostly containing neurosecretory granules, are frequently found between the cells. The active corpus allatum is remarkable by the numerous lipid droplets and the abundance of tubular agranular reticulum. The reticulum sometimes forms aggregates from which vacuoles are budded off. The vacuoles lose their membrane, at the same time becoming slightly electron opaque, thus being transformed into lipid droplets. It is tentatively postulated that the hormone (or a precursor) is synthesized in the tubules of the agranular reticulum, collected in the vacuoles, and, when the membrane disintegrates, it is dissolved in lipid. The lipid droplets are thought to be released into the haemolymph through the surface of the gland or via intercellular channels. The inactive corpus allatum of the six days old sugar fed flies is small and more or less shrunken. The agranular reticulum is poorly developed, vacuoles are small, and lipid droplets few. The reticulum tends to form whorls, which eventually may possibly be transformed into myelin figures.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00343984
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