| First Author | Alloatti G | Year | 2005 |
| Journal | FEBS Lett | Volume | 579 |
| Issue | 1 | Pages | 133-40 |
| PubMed ID | 15620702 | Mgi Jnum | J:95369 |
| Mgi Id | MGI:3525913 | Doi | 10.1016/j.febslet.2004.11.059 |
| Citation | Alloatti G, et al. (2005) Phosphoinositide 3-kinase gamma controls autonomic regulation of the mouse heart through Gi-independent downregulation of cAMP level. FEBS Lett 579(1):133-40 |
| abstractText | Cardiac beta-adrenergic and the muscarinic receptors control contractility and heart rate by triggering multiple signaling events involving downstream targets like the phosphoinositide 3-kinase gamma (PI3Kgamma). We thus investigated whether the lack of PI3Kgamma could play a role in the autonomic regulation of the mouse heart. Contractility and ICaL of mutant cardiac preparations appeared increased in basal conditions and after beta-adrenergic stimulation. However, basal and beta-adrenergic stimulated heart rate were normal. Conversely, muscarinic inhibition of heart rate was reduced without alteration of the Gbetagamma-dependent stimulation of IK,ACh current. In addition, muscarinic-mediated anti-adrenergic effect on papillary muscle contractility and ICaL was significantly depressed. Consistently, cAMP level of PI3Kgamma-null ventricles was always higher than wild-type controls. Thus, PI3Kgamma controls the cardiac function by reducing cAMP concentration independently of Gi-mediated signaling. |
