Effects of anthopleurin-Q on myocardial hypertrophy in rats and physiologic properties of isolated atria in guinea pigs.
Abstract
AIM: To study effects of anthopleurin-Q (AP-Q) on myocardial hypertrophy in rats
and isolated atria in guinea pigs.
METHODS: Two myocardial hypertrophy models in rats were established, one
introduced by levothyroxine, the other by stenosis of abdominal aorta. Cardiac
myocytes morphometry and functional experiments were employed to investigate
effects of AP-Q.
RESULTS: Low dose of AP-Q (1 microg/kg/d, ip) reduced morphologic changes of
myocardial hypertrophy in both rat models. While high dose of AP-Q (10
microg/kg/d, ip) did not, and caused mild hydropic degeneration in
cardiomyocytes. High concentration of AP-Q (30 nmol/L) enhanced the
contractility, raised automaticity, and prolonged the functional refractory
period (FRP) in isolated left atria of guinea pigs; higher concentration (100
nmol/L) triggered arrhythmia in right atria; low concentration of AP-Q (1
nmol/L)did not affect any myocardial properties above.
CONCLUSION: Low dose of AP-Q without inotropic effect can hinder the experimental
myocardial hypertrophy in rats; high dose with positive inotropic effect may be
responsible for its toxic reaction.
Keywords:
and isolated atria in guinea pigs.
METHODS: Two myocardial hypertrophy models in rats were established, one
introduced by levothyroxine, the other by stenosis of abdominal aorta. Cardiac
myocytes morphometry and functional experiments were employed to investigate
effects of AP-Q.
RESULTS: Low dose of AP-Q (1 microg/kg/d, ip) reduced morphologic changes of
myocardial hypertrophy in both rat models. While high dose of AP-Q (10
microg/kg/d, ip) did not, and caused mild hydropic degeneration in
cardiomyocytes. High concentration of AP-Q (30 nmol/L) enhanced the
contractility, raised automaticity, and prolonged the functional refractory
period (FRP) in isolated left atria of guinea pigs; higher concentration (100
nmol/L) triggered arrhythmia in right atria; low concentration of AP-Q (1
nmol/L)did not affect any myocardial properties above.
CONCLUSION: Low dose of AP-Q without inotropic effect can hinder the experimental
myocardial hypertrophy in rats; high dose with positive inotropic effect may be
responsible for its toxic reaction.