ischaemic preconditioning of the human heart. - Leicester Research ...

4.2.5 Statistical Analysis
All data are presented as mean ± SEM. All values were compared by ANOVA with
application of a post hoc Tukey's test. Ap value of < 0.05 was considered statistically
significant.
4.3 RESULTS
All samples entering the studies completed the applied experimental protocol and were
included in the analysis. A dose-response analysis (0 to 5 mM) based on
both CK leakage
and MTT reduction, revealed that diazoxide and pinacidil were found to be most
protective at a dose of 100 ýt! Vl and 0.5 mM respectively. Diazoxide lost its protective
effect at doses > SOO ýLM and pinacidil at doses >- I mM (see Figures 4.2 and 4 3). At the
above optimal doses, the greatest degree of protection was afforded when the K, xui,
openers was applied for 10 min before ischemia (pretreatment) followed by wash-out.
Glibenclamide abolished the protective effects of preconditioning at doses > 10 pM (see
Figure 4.4). A dose response analysis for 5-HD (Figure 4.5) was performed between
concentrations of 0-10 mM. The minimal effective concentration for 5-HD which
abolished protection afforded by preconditioning was I mM. The dose-response
analysis
for HMR 1883 (Figure 4.6) revealed that concentrations between the ranges 0 to 100 pM
had no effect on the protection afforded by preconditioning. Again pretreatment with
these drugs for 10min before ischemia was the most effective protocol.
95