Background/Aim. Stevioside is a glycoside that supposedly possesses a number
of pharmacodynamic effects such as anti-infective, hypoglycemic, along with
the beneficial influence on the cardiovascular system. The aim of this study
was to determine the effect of rats pretreatment with aqueous solution of
stevioside on pharmacological actions of adrenaline, metoprolol and
verapamil. Methods. Rats were administered (intraperitoneally 200 mg/kg/day)
stevioside as aqueous solution or physiological saline in the course of 5
days, then anaesthetized with urethane and the first ECG recording was made.
The prepared jugular vein was connected to an infusion pump with adrenaline
(0.1 mg/mL), verapamil (2.5 mg/mL) or metoprolol (1 mg/mL). Control animals,
pretreated with saline, in addition to the mentioned drugs, were also infused
with the solution of stevioside (200 mg/mL) in the course of recording ECG.
Results. The infusion of stevioside produced no significant changes in ECG,
even at a dose exceeding 1,600 mg/kg. In the control group, a dose of
adrenaline of 0.07 ? 0.02 mg/kg decreased the heart rate, whereas in the
steviosidepretreated rats this occurred at a significantly higher dose (0.13
? 0.03 mg/kg). In stevioside-pretreated rats, the amount of verapamil needed
to produce the decrease in heart rate was significantly lower compared to the
control. The pretreatment with stevioside caused no significant changes in
the parameters registered on ECG during infusion of metoprolol. Conclusion.
The results suggest that pretreatment with stevioside may change the effect
of adrenaline and verapamile on the heart rate.
Implications of the use of hydroxychloroquine on cardioactive drugs