Previous studies indicated an important role of the proteins Gaq and Ga₁₁ in the development of cardiac hypertrophy. Especially Gaq is required for a normal heart development during embryogenesis.

In transgenic mice we combined a non-specific Ga₁₁ knockout with a heart specific inducible Gaq knockout. We performed our experiments in four different genotypes: Gaq/a₁₁ double knockout, Gaq single knockout, Ga₁₁ single knockout and wild type mice. The following cardiovascular parameters were analyzed: IVS, LVAW LVPW, LVID, EF, FS, LV volume, LV Mass, MV velocity derived from echocardiography and long-term ECG parameters (arrhythmic events) as well as blood pressure from implanted telemetric sensors. These non-invasive measurements were performed on mice at the age of 8, 11, 14, 20 and 54 weeks.

The investigations revealed a different behavior of the four genotypes regarding heartbeat, arrhythmias, mitral valve velocity, heart size and volume in particular during the fist three month after the induction of the Gaq-knockout while these differences are likely to disappear in the following months.

Our results reveal novel insights into the physiological and pathophysiological role of Gaq and Ga₁₁ in the cardiac performance and we created a basal characterization for further (invasive) disease models in these transgenic mouse lines.

This research was supported by the DFG (KFO-196).