The same procedure as described above was repeated at an S1-S1 interval of 200 and 180 ms to evaluate the rate dependency of tedisamil and D-sotalol effects on refractoriness.
Sinus node recovery time: To evaluate sinus node recovery time, the heart was paced for 30 s at an S1-S1 interval of 200 ms in the sinus node area, after which the stimulation was stopped. The interval between the last stimulus induced and the first spontaneously appearing atrial signal was defined as sinus node recovery time.
Drugs: Tedisamil (Solvay Pharma Deutschland, Hannover, Germany) and D-sotalol (Parke Davis, Freiburg, Germany) were dissolved in distilled water. Drug stock solutions were freshly prepared every day. Concentrations of 1, 3 and 10 |J.M were used. During all experiments, the compound was continuously injected into the Tyrode’s solution by a perfusion pump, near the aorta, to avoid unspecific binding to the perfusion system. Control measurements were done during perfusion with Tyrode’s solution. A perfusion period of 15 mins for either drug was given to reach steady state. Statistical analysis: All values are expressed as mean ± SEM. Results were statistically analyzed by Student’s t test or Wilcoxon’s test after a test of homogeneity of variance for single comparisons or repeated measures ANOVA, followed by Dunnett’s test for comparisons between control and increasing concentrations of either tedisamil or D-sotalol using a statistical software package (Sigmastat, version 1.0, Jandel Scientific, Erkrath, Germany). Most reliable pharmacy can offer Xopenex Inhaler Dosage at our place always charging you a lot less.