title: An electron microscopic and biochemical study of the effects of cyclic 3', 5'-AMP, ergotamine or propranolol on the lysosomes of newborn rat hepatocytes.
abstract: The effects of cyclic 3',5'-AMP, ergotamine or propranolol on newborn rat liver were studied by using biochemical assays, electron microscopy and quantitative morphometry. Cyclic AMP enhanced the normal postnatal rise in the glycogen-hydrolysing activity of acid alpha 1, 4 glucosidase but had no effect on the maltose-hydrolysing activity of the enzyme. The results suggest that these activities may be due to different enzymes. Propranolol prevented the postnatal increase in the glycogen-hydrolysing activity of acid glucosidase and the breakdown of lysosomal glycogen, indicating that these phenomena represent beta-adrenergic functions in newborn rats. Ergotamine also inhibited the postnatal increase in this activity and the lysosomal glycogen mobilization. A reasonable explanation for these results is that ergotamine interferes with the action or formation of cyclic AMP.
authors.affiliation: Department of Anatomy, Histology and Embryology, Medical School, University of Ioannina, Greece.
authors.forename: A O
authors.initials: AO
authors.lastname: Kotoulas
authors.forename: O B
authors.initials: OB
authors.lastname: Kotoulas
authors.forename: S
authors.initials: S
authors.lastname: Kalamidas
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001343:Autophagy; D000242:Cyclic AMP / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D004878:Ergotamine / Q000494:pharmacology*; D006003:Glycogen / Q000378:metabolism; D008099:Liver / Q000187:drug effects* / Q000648:ultrastructure; D008247:Lysosomes / Q000187:drug effects* / Q000648:ultrastructure; D008320:Maltose / Q000378:metabolism; D011433:Propranolol / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D014617:Vacuoles / Q000187:drug effects / Q000648:ultrastructure; D000520:alpha-Glucosidases / Q000187:drug effects
chemical_list: D008320:Maltose; D006003:Glycogen; D011433:Propranolol; D000242:Cyclic AMP; D000520:alpha-Glucosidases; D004878:Ergotamine