Key Points
- To determine whether early administration of propranolol reduces mortality and modifies sarcoplasmic reticulum calcium transport in an animal model of inherited congestive cardiomyopathy.
- Administered propranolol (2 mg/kg/day) or no treatment for 1 month to one-day-old inbred cardiomyopathic turkeys and commercial controls.
- Tracked cumulative mortality up to 28 days and isolated cardiac sarcoplasmic reticulum to measure Ca2+ uptake, Ca2+ binding, and Ca2+-stimulated ATPase activity at 10 and 28 days of age.
- Propranolol significantly lowered mortality between 5 and 15 days of age in inbred birds, but 28-day cumulative mortality reached 29% in treated versus 32% in untreated inbred birds, compared to 5% in commercial controls.
- At 10 days of age, Ca2+ uptake and Ca2+ binding in treated inbred birds dropped to 56% and 83% of untreated inbred levels, respectively, before equalizing by day 28.
- Ca2+-stimulated ATPase activity remained significantly elevated in treated inbred birds at both 10 and 28 days compared to untreated controls, indicating an uncoupling of calcium transport.
Structured PICO
Does early propranolol treatment reduce mortality and alter Ca2+ transport in an animal model of congestive cardiomyopathy?
PPopulationOne-day-old young turkeys inbred for congestive cardiomyopathy and commercial turkeys
IInterventionPropranolol 2 mg/kg/day for 1 month
CComparatorUntreated inbred birds and untreated commercial birds
OOutcomeMortality (5 to 15 days and 28-day cumulative) and Ca2+ transport in isolated cardiac sarcoplasmic reticulum (Ca2+ uptake, binding, and ATPase activity)hard clinical
In a turkey model of congestive cardiomyopathy, early propranolol treatment delayed early mortality but did not improve 1-month survival, and altered sarcoplasmic reticulum calcium transport.