The role of mitochondrial ATP-sensitive potassium channels on cardiovascular effects of thiopental and ketamine in rats.

Abstract

We aimed to investigate whether mitochondrial ATP-sensitive potassium (mitoKATP) channels play any role on cardiovascular effects of thiopental (TP) or ketamine (K) anesthesia in rats. mitoKATP channels are the end-effectors of cardioprotection induced by some anesthetics. TP and K are the most frequently used anesthetics with their own cardiovascular effects in experimental studies. To the best of our knowledge, there is no study investigating the cardiovascular effects of TP and K associated with mitoKATP channels. The experimental groups: TP control, K/Xylazine (X) control, TP+5-hydroxydecanoate (5-HD; mitoKATP channel blocker) and K/X+5-HD. Mean arterial blood pressure (MABP), heart rate (HR) and standard limb lead II ECG were recorded and arrhythmia parameters were evaluated. Blockage of mitoKATP channels by 5-HD increased MABP and decreased HR in the TP+5-HD and K/X+5-HD groups, respectively. 5-HD caused an increase in ventricular ectopic beat (VEB) incidence. Moreover, VEB incidence was significantly different in TP+5-HD (100%) than K/X+5-HDgroup (66.6%) and ventricular tachycardia was only seen in TP+5-HD (incidence was 88.3%). mitoKATP channels play different roles in influencing cardiovascular effects of K/X and TP anesthesia in rats. The differences in hemodynamic parameters and arrhythmia scores of these anesthetics should be considered when they are used in an experimental study associated with mitoKATP channels (Fig. 3, Ref. 35).