title: Effects of low temperature on the formation of secretion granules in the Golgi apparatus of granular cells of the frog urinary bladder.
abstract: The formation of secretion granules has been studied in the Golgi apparatus of granular epithelial cells of frog urinary bladders maintained at room temperature or cooled at 4 degrees C for various lengths of time. In control animals, the Golgi apparatus was composed of the following stacked elements: subjacent to the cis-element made up of anastomosed tubules, two elements in the mid-compartment consisted of flattened saccules interconnected by tubules. On the trans-face, two or three sacculo-tubular elements were slightly dilated by an electron dense granular material. In the trans-Golgi elements, this material was segregated into dilatations of various sizes and shapes which are continuous with flattened portions devoid of stained material. In the trans-Golgi region, free irregular progranules, seemingly formed by rupture of the trans-most Golgi elements. In granular cells examined after 4 h at 4 degrees C, all Golgi compartments were affected by the low temperature. The cis-half portion of the Golgi apparatus consisted mainly of anastomosed membranous tubules and the cis-element was no longer recognizable. The trans-compartment was reduced to a few flattened saccules with progranules hardly visible on their trans-aspect. At later time intervals, there was a progressive reconstitution of the cis-zone while saccular elements started to pile up in the trans-compartment. At 24 h, the trans-compartment comprised six to eight saccular elements which showed irregular dilatations filled with granular material separated by large flattened portions. These various observations were interpreted as indicating that the trans-compartment was a dynamic structure undergoing continuous renewal.
authors.affiliation: Département de Biologie Cellulaire et Moléculaire du CEA, Centre d'Etudes Nucléaires de Saclay, Gif-sur-Yvette, France.
authors.forename: A
authors.initials: A
authors.lastname: Rambourg
authors.forename: Y
authors.initials: Y
authors.lastname: Clermont
authors.forename: M
authors.initials: M
authors.lastname: Pisam
authors.forename: P
authors.initials: P
authors.lastname: Ripoche
mesh_terms: D000818:Animals; D003080:Cold Temperature; D003594:Cytoplasmic Granules / Q000378:metabolism* / Q000648:ultrastructure; D006056:Golgi Apparatus / Q000378:metabolism* / Q000648:ultrastructure; D008854:Microscopy, Electron; D011893:Rana esculenta; D013696:Temperature; D001743:Urinary Bladder / Q000166:cytology / Q000378:metabolism* / Q000648:ultrastructure