Phenotypes associated with this allele
|
Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Scn5atm1Agrc mutation
(0 available);
any
Scn5a mutation
(104 available)
|
|
|
Morphology of E10.5 control and Scn5atm1Agrc/Scn5atm1Agrc hearts
mortality/aging
|
• observe no heart contractions beyond E11.5 and see autolysis of embryos
|
cardiovascular system
|
• reduction in the number of thin, spindle-like cardiomyocytes
|
|
• reduction in chamber size, however, the endocardial cushions of the atrioventricular canal, the common atrial chamber, and the truncus arteriosus all appear normal
|
|
• reduction in trabeculation of the ventricular wall
|
|
• show uncoordinated contractions at E10.5
|
embryo
growth/size/body
muscle
|
• reduction in the number of thin, spindle-like cardiomyocytes
|
|
• reduction in trabeculation of the ventricular wall
|
|
• show uncoordinated contractions at E10.5
|
Allelic Composition |
Scn5atm1Agrc/Scn5a+
|
|
Genetic Background |
involves: 129 |
|
Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Scn5atm1Agrc mutation
(0 available);
any
Scn5a mutation
(104 available)
|
|
|
cardiovascular system
|
• old but not young mutants show extensive fibrosis of the ventricular myocardium (in the left and right ventricular free walls and in the interventricular septum)
• although young mutants do not exhibit ventricular fibrosis, they do show increased perivascular fibrosis which becomes massive with age
|
|
• show slight but significant bradycardia
|
|
• mutants exhibit a higher incidence of ventricular tachycardia than wild-type (25% vs. 6%)
• ventricular tachycardias begin at earlier times in the right ventricular outflow tract than at the base of the left ventricle
• mutant hearts exhibit abnormal electrophysiological properties of the right ventricle at the right ventricle outflow tract, showing increased heterogeneities in action potential duration, ventricular effective refractory periods, electrogram duration ratios and response latencies that correlate with an increased incidence of discordant alternans and with steeper restitution slopes
|
|
• PR intervals progressively prolong with age (from 3 to 71 weeks)
|
|
• P-wave intervals progressively prolong with age (from 3 to 71 weeks)
|
|
• QRS intervals progressively prolong with age (from 3 to 71 weeks)
|
|
• QTrc and QTc intervals are prolonged due to prolongation of the QRS interval
|
Allelic Composition |
Scn5atm1Agrc/Scn5a+
|
|
Genetic Background |
involves: 129 * C57BL/6J |
|
Find Mice |
Using the International Mouse Strain Resource (IMSR)
Mouse lines carrying:
Scn5atm1Agrc mutation
(0 available);
any
Scn5a mutation
(104 available)
|
|
|
cardiovascular system
|
• after aortic cannulation and Langendorff-perfusion, whole isolated hearts show marked rate slowing
|
|
• display ventricular tachycardia during continuous pacing or after the delivery of S2 stimuli at shorter S1-S2 intervals
|
|
• exhibit a 50% reduction in sodium conduction, leading to impaired action potential propagation and atrioventricular conduction, delayed intramyocardial conduction, increased ventricular refractoriness, and ventricular tachycardia with characteristics of reentrant excitation
|
|
• prolonged PR interval, however QT interval is unchanged
|
|
• peak current densities of myocytes are reduced, indicating reduced sodium channel density
|