title: Biochemical changes and their relationship with morphological and functional findings in pig heart subjected to lasting volume overload: a possible role of acylphosphatase in the regulation of sarcoplasmic reticulum calcium pump.
abstract: We evaluated the changes in sarcoplasmic reticulum (SR) function and the parallel hemodynamic and morphological modifications in a heart subjected to volume overload. We also determined the levels of acylphosphatase, a cytosolic enzyme, that could play a regulatory effect on SR Ca(2+) pump by hydrolyzing the phosphorylated intermediate of this transport system. For this, swine hearts were subjected to volume overload by aorta-cava shunt for 1, 2, or 3 months. Changes in heart contractility reflected modifications of SR function, whose reduction after 1 month of overload was followed by a gradual recovery. A decrease in SERCA2a protein and mRNA content was shown from 1 month and remained for the following 2 months. Phospholamban content and its phosphorylation status were not modified. Acylphosphatase was unchanged at 1 month, but at 2 months this enzyme exhibited an increased activity, protein and mRNA expression. Morphological alterations consisting of the cytoskeletal architectures, intermyofibrillar oedema, swollen mitochondria and abnormality of the membrane system (T-tubule and SR cisternae) were particularly evident after 1 month but almost disappeared after 3 months. These results suggest that our overloaded hearts underwent a substantial recovery of their structural and biochemical properties at 3 months after surgery. A possible involvement of acylphosphatase in the modification of SR function is discussed.
authors.affiliation: Department of Biochemical Sciences, Viale Morgagni 50, 50134 Florence, Italy.
authors.forename: C
authors.initials: C
authors.lastname: Nediani
authors.forename: L
authors.initials: L
authors.lastname: Formigli
authors.forename: A M
authors.initials: AM
authors.lastname: Perna
authors.forename: A
authors.initials: A
authors.lastname: Pacini
authors.forename: V
authors.initials: V
authors.lastname: Ponziani
authors.forename: P A
authors.initials: PA
authors.lastname: Modesti
authors.forename: L
authors.initials: L
authors.lastname: Ibba-Manneschi
authors.forename: S
authors.initials: S
authors.lastname: Zecchi-Orlandini
authors.forename: C
authors.initials: C
authors.lastname: Fiorillo
authors.forename: C
authors.initials: C
authors.lastname: Cecchi
authors.forename: P
authors.initials: P
authors.lastname: Liguori
authors.forename: G
authors.initials: G
authors.lastname: Fratini
authors.forename: S
authors.initials: S
authors.lastname: Vanni
authors.forename: P
authors.initials: P
authors.lastname: Nassi
mesh_terms: D017766:Acid Anhydride Hydrolases / Q000378:metabolism*; D000818:Animals; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D004452:Echocardiography; D006321:Heart / Q000503:physiopathology*; D006439:Hemodynamics; D006940:Hyperemia / Q000473:pathology* / Q000503:physiopathology*; D008854:Microscopy, Electron; D009206:Myocardium / Q000201:enzymology / Q000473:pathology*; D012519:Sarcoplasmic Reticulum / Q000201:enzymology*; D013552:Swine; D000097024:Acylphosphatase
chemical_list: D017766:Acid Anhydride Hydrolases; D000252:Calcium-Transporting ATPases; D000097024:Acylphosphatase