| dc.creator | Mundiña-Weilenmann, Cecilia | |
| dc.creator | Vittone, Leticia Beatriz | |
| dc.creator | Ortale, Manuel | |
| dc.creator | Chiappe de Cingolani, Gladys Ethel | |
| dc.creator | Mattiazzi, Alicia Ramona | |
| dc.date | 1996-12-27 | |
| dc.date | 2021-08-23T15:33:05Z | |
| dc.date.accessioned | 2023-07-15T02:44:39Z | |
| dc.date.available | 2023-07-15T02:44:39Z | |
| dc.identifier | http://sedici.unlp.edu.ar/handle/10915/123153 | |
| dc.identifier | issn:0021-9258 | |
| dc.identifier.uri | https://repositorioslatinoamericanos.uchile.cl/handle/2250/7463110 | |
| dc.description | Phosphorylation site-specific antibodies, quantification of <sup>32</sup>P incorporation into phospholamban, and simultaneous measurements of mechanical activity were used in Langendorff-perfused rat hearts to provide further insights into the underlying mechanisms of phospholamban phosphorylation. Immunological detection of phospholamban phosphorylation sites showed that the isoproterenol concentration-dependent increase in phospholamban phosphorylation was due to increases in phosphorylation of both Ser<sup>16</sup> and Thr<sup>17</sup> residues. When isoproterenol concentration was increased at extremely low Ca²⁺ supply to the myocardium, phosphorylation of Thr<sup>17</sup> was virtually absent. Under these conditions, <sup>32</sup>P incorporation into phospholamban, due to Ser<sup>16</sup>, decreased by 50%. Changes in Ca²⁺ supply to the myocardium either at constant β-adrenergic stimulation or in the presence of okadaic acid, a phosphatase inhibitor, exclusively modified Thr<sup>17</sup> phosphorylation. Changes in phospholamban phosphorylation due to either Ser<sup>16</sup> and/or Thr<sup>17</sup> were paralleled by changes in myocardial relaxation. The results indicate that cAMP- (Ser<sup>16</sup>) and Ca²⁺-calmodulin (Thr<sup>17</sup>)-dependent pathways of phospholamban phosphorylation can occur independently of each other. However, in the absence of β-adrenergic stimulation, phosphorylation of Thr<sup>17</sup> could only be detected after simultaneous activation of Ca²⁺-calmodulin-dependent protein kinase and inactivation of phosphatase. It is suggested that under physiological conditions, this requisite is only filled by cAMP-dependent mechanisms. | |
| dc.description | Facultad de Ciencias Médicas | |
| dc.description | Centro de Investigaciones Cardiovasculares | |
| dc.format | application/pdf | |
| dc.format | 33561-33567 | |
| dc.language | en | |
| dc.rights | http://creativecommons.org/licenses/by/4.0/ | |
| dc.rights | Creative Commons Attribution 4.0 International (CC BY 4.0) | |
| dc.subject | Medicina | |
| dc.subject | Biología | |
| dc.subject | Rats | |
| dc.subject | Phosphorylation | |
| dc.subject | Heart | |
| dc.subject | Phospholamban | |
| dc.subject | Isoproterenol | |
| dc.title | Immunodetection of phosphorylation sites gives new insights into the mechanisms underlying phospholamban phosphorylation in the intact heart | |
| dc.type | Articulo | |
| dc.type | Articulo | |
