title: Biophysical characteristics of oxytocin secretory granules isolated from ovine corpora lutea.
abstract: Luteal oxytocin-containing secretory granules have been isolated and characterized in terms of their physicochemical parameters. The isopynic sedimentation density (1.03 +/- 0.003 g/ml) and sedimentation coefficient (1670 S, 0.32 mol sucrose/l, 4 degrees C) of these granules have been estimated. Based upon these estimates, the average vesicle diameter (258 +/- 17 nm) and vesicle weight (9.92 +/- 0.67 fg/vesicle) were calculated. The exchangeable water content (58.2%) of these granules was determined using density gradients prepared with deuterium oxide. Luteal oxytocin-containing granules displayed similar physicochemical characteristics to those reported for neurohypophysial peptide-containing granules, with the exception of particle size. Luteal granules were 1.3 times greater in diameter than neurohypophysial granules.
authors.affiliation: Department of Physiology, Monash University, Clayton, Victoria, Australia.
authors.forename: G E
authors.initials: GE
authors.lastname: Rice
mesh_terms: D000818:Animals; D055592:Biophysical Phenomena; D001703:Biophysics; D002458:Cell Fractionation; D002500:Centrifugation, Isopycnic; D003338:Corpus Luteum / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure*; D003594:Cytoplasmic Granules / Q000187:drug effects / Q000378:metabolism / Q000648:ultrastructure*; D005260:Female; D010121:Oxytocin / Q000378:metabolism*; D010904:Pituitary Gland, Posterior / Q000648:ultrastructure; D011189:Potassium Chloride / Q000494:pharmacology; D012756:Sheep
chemical_list: D010121:Oxytocin; D011189:Potassium Chloride