The present study was undertaken to investigate, in an animal model, the relationship between sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) activity, phospholamban phosphorylation, acylphosphatase activity, and hemodynamic changes that occur in the early phase of pressure overload. In 54 study-group pigs, weighing 40 ± 5 kg each, an aortic stenosis was created with a band of umbilical tape tied around the aorta; 18 sham-operated pigs formed our control group. Eight animals (6 study and 2 control) were randomly assigned to each experimental time (0.5, 3, 6, 12, 24, 48, 72, 96, and 168 hr). All indices of left ventricular function declined significantly, with a peak at 6 hr and a return to baseline at 168 hr. At each observational time, SERCA2a activity, Ca2+ uptake, and acylphosphatase activity rose significantly, with a maximum increase at 6 hr. These changes indicated a higher expression of these proteins; conversely, phospholamban did not show significant changes in its concentration or in its phosphorylation status. Nuclear proto-oncogene c-fos expression rose at 6 hr. A strong inverse correlation was found when Ca2+-ATPase activity, Ca2+-ATPase expression, Ca2+ uptake, and acylphosphatase were compared with indices of systolic function. In our model of induced pressure overload, an initial phase of depressed myocardial contractility was accompanied by an increased sarcoplasmic reticulum function and by higher Ca2+-ATPase and Ca2+ uptake activities mediated by acylphosphatase. This new finding of Ca2+ homeostasis might indicate a compensatory mechanism for mechanical stress. Further studies are needed to confirm our findings.
Early Hemodynamic and Biochemical Changes in Overloaded Swine Ventricle / Sandro Gelsomino, Fabiana Lucà, Chiara Nediani, Sandra Zecchi Orlandini, Daniele Bani, Antonio S Rubino, Attilio Renzulli, Roberto Lorusso, Andrea Consolo, Antonino Lo Cascio, Jos Maessen, Gian Franco Gensini. - In: TEXAS HEART INSTITUTE JOURNAL. - ISSN 0730-2347. - STAMPA. - 40:(2013), pp. 235-245.
Early Hemodynamic and Biochemical Changes in Overloaded Swine Ventricle.
Sandro Gelsomino
Membro del Collaboration Group
;Chiara NedianiMembro del Collaboration Group
;Sandra Zecchi OrlandiniMembro del Collaboration Group
;Daniele BaniMembro del Collaboration Group
;Gian Franco GensiniMembro del Collaboration Group
2013
Abstract
The present study was undertaken to investigate, in an animal model, the relationship between sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) activity, phospholamban phosphorylation, acylphosphatase activity, and hemodynamic changes that occur in the early phase of pressure overload. In 54 study-group pigs, weighing 40 ± 5 kg each, an aortic stenosis was created with a band of umbilical tape tied around the aorta; 18 sham-operated pigs formed our control group. Eight animals (6 study and 2 control) were randomly assigned to each experimental time (0.5, 3, 6, 12, 24, 48, 72, 96, and 168 hr). All indices of left ventricular function declined significantly, with a peak at 6 hr and a return to baseline at 168 hr. At each observational time, SERCA2a activity, Ca2+ uptake, and acylphosphatase activity rose significantly, with a maximum increase at 6 hr. These changes indicated a higher expression of these proteins; conversely, phospholamban did not show significant changes in its concentration or in its phosphorylation status. Nuclear proto-oncogene c-fos expression rose at 6 hr. A strong inverse correlation was found when Ca2+-ATPase activity, Ca2+-ATPase expression, Ca2+ uptake, and acylphosphatase were compared with indices of systolic function. In our model of induced pressure overload, an initial phase of depressed myocardial contractility was accompanied by an increased sarcoplasmic reticulum function and by higher Ca2+-ATPase and Ca2+ uptake activities mediated by acylphosphatase. This new finding of Ca2+ homeostasis might indicate a compensatory mechanism for mechanical stress. Further studies are needed to confirm our findings.File | Dimensione | Formato | |
---|---|---|---|
Gelsomino et al-compresso.pdf
accesso aperto
Tipologia:
Pdf editoriale (Version of record)
Licenza:
Tutti i diritti riservati
Dimensione
720.98 kB
Formato
Adobe PDF
|
720.98 kB | Adobe PDF |
I documenti in FLORE sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.