title: Morphological and cytochemical studies on the secretory granules of the pyloric caeca of the starfish, Asterias amurensis.
abstract: A fraction rich in secretory granules was prepared from the pyloric caeca of Asterias amurensis by sucrose density gradient centrifugation. The freshly prepared fraction exhibited no casein-hydrolyzing activity, but showed nine times as much specific activity as that of tissue homogenates after incubation at 37 degrees C for thirty minutes. Electron microscopy showed that the secretory granules were membrane-bound granules measuring 0.5-2.0 mu in diameter and contained dense and/or light amorphous substances.
mesh_terms: D000818:Animals; D002432:Cecum / Q000201:enzymology / Q000648:ultrastructure; D002458:Cell Fractionation; D004792:Enzyme Precursors / Q000378:metabolism; D008854:Microscopy, Electron; D009940:Organoids / Q000648:ultrastructure; D010447:Peptide Hydrolases / Q000378:metabolism*; D011708:Pylorus / Q000201:enzymology / Q000648:ultrastructure; D013215:Starfish / Q000033:anatomy & histology / Q000201:enzymology / Q000648:ultrastructure*
chemical_list: D004792:Enzyme Precursors; D010447:Peptide Hydrolases