RESUMO
The effect of α-methyl-5-hydroxytryptamine maleate, an agonist of 5-HT2B serotonin receptors, on the pumping function of the heart was examined in rats with forced motor behavior. At rest, swim-trained rats demonstrated lower HR and greater stroke volume and cardiac output than untrained rats. The agonist decreased HR, stroke volume, and cardiac output in 21- and 70-day-old swim-trained rats, but not in 100- and 200-day-old rats.
Assuntos
Coração/efeitos dos fármacos , Agonistas do Receptor 5-HT2 de Serotonina/farmacologia , Serotonina/análogos & derivados , Animais , Débito Cardíaco/efeitos dos fármacos , Coração/fisiologia , Frequência Cardíaca/efeitos dos fármacos , Ratos , Serotonina/farmacologia , Volume Sistólico/efeitos dos fármacosRESUMO
We studied cardiac pumping function in the offspring of rats subjected to swimming exercise and the offspring of untrained rats. The rat pups were adapted for swimming with stepwise increasing load from day 21 to 70 life. At the age of 21 and 70 days, offspring of trained rats showed lower HR and significantly higher stroke volume and cardiac output than offspring of untrained rats. Agonist of 5-HT(2)-receptors α-methyl-5-hydroxytryptamine maleate (30 µg/kg) reduced enhanced stroke volume in trained offspring born by trained mothers. In trained offspring of untrained rats, the agonist had more pronounced effect on HR.
