Table 1.

Effect of isoproterenol treatment in E2F1 knockout mice. Echocardiography analysis of E2F1 +/+ wild type mice and E2F1 -/- knockout mice before (pre) and after (post) treatment with isoproterenol. 2-way ANOVA analysis comparing E2F1 +/+ to E2F1 -/- (genotype), pre and post drug treatment (drug) and the interaction between genotype and drug (interaction). Data are expressed as the mean +/- SD. Significance was determined when p<0.05 and is indicated not significant (NS) if value was higher than 0.05.

	E2F1 +/+	(n=6)	E2F1 -/-	(n=6)		2-way ANOVA
	Pre	Post	Pre	Post	Genotype	Drug	Interaction
Weight (g)	31.1±2.9	32.7±2.4	25.6±3	27.3±2.4	p<0.05	NS	NS
HR (bpm)	410±60	538±46	425±33	506±54	NS	p<0.05	NS
LA (cm)	0.21±0.02	0.21±0.02	0.21±0.02	0.21±0.02	NS	NS	NS
MPI	0.36±0.03	0.34±0.06	0.31±0.02	0.38±0.08	NS	NS	NS
CO (cc)	16±4	26±2	15±2	26±8	NS	p<0.05	NS
EDD (cm)	0.36±0.02	0.38±0.03	0.34±0.02	0.32±0.03	p<0.05	NS	p<0.05
ESD (cm)	0.21±0.03	0.17±0.02	0.17±0.02	0.14±0.02	p<0.05	p<0.05	NS
FS	0.42±0.07	0.56±0.06	0.5±0.04	0.56±0.03	p<0.05	p<0.05	NS
E/A	1.18±0.11	1.11±0.36	1.22±0.2	1.11±0.28	NS	NS	NS
LVMI (mg/g)	4.6±0.5	6.8±1.8	5.2±1.3	6.8±1.3	NS	p<0.05	NS
RWT	0.59±0.07	0.69±0.08	0.62±0.17	0.88±0.17	NS	p<0.05	NS
Vcf	6.5±2.3	12.9±2.2	8.8±2	10.9±1.6	NS	p<0.05	p<0.05

Abbreviations: heart rate (HR), left atrial (LA), myocardial performance index (MPI), cardiac output (CO), end diastolic dimension (EDD), end systolic dimension (ESD), fractional shortening (FS), the ratio between early and late ventricular filling velocity (E/A), left ventricular mass index (LVMI), relative wall thickness (RWT), velocity of circumferential fiber shortening (Vcf).