Mouse Genome Informatics
hm1
     Casq2tm1Klmn/Casq2tm1Klmn
involves: 129S1/Sv * 129X1/SvJ * C57BL/6
Key:
♀ phenotype observed in females WTSI Wellcome Trust Sanger Institute
♂ phenotype observed in males Euro Europhenome
N normal phenotype

Junctional sarcoplasmic reticulum lacks its visible content, and overall sarcoplasmic reticulum volume is increased in ventricular myocytes of Casq2tm1Klmn/Casq2tm1Klmn mice

cardiovascular system
increased heart weight ( J:114621 )
• approximately 10% increase in heart to body weight ratio
thick ventricular wall ( J:114621 )
• modest but statistically significant increase in ventricular wall thickness
decreased heart rate ( J:114621 )
• display a significantly slower heart rate but normal cardiac contractility, normal left-ventricular cavity size, and unchanged ECG parameters
• homozygous mice were viable and fertile
ventricular tachycardia ( J:114621 )
• exposure to catecholamine in homozygous mice myocytes caused polymorphic nonsustained ventricular tachycardia, a phenocopy of the human arrhythmias
abnormal myocardial fiber physiology ( J:114621 )
• exhibited striking increases in sarcoplasmic reticulum volume and surface area
• exposure to catecholamines caused increased diastolic sarcoplasmic reticulum Ca2+ leak