Preservation of TSPO by chronic intermittent hypobaric hypoxia confers antiarrhythmic activity.
Bottom Line: TSPO stimulation or inhibition affected the arrhythmias incidence in normoxic rats, but did not change the CIHH-mediated antiarrhythmic effects.The preservation of TSPO activity by CIHH also contributed to the maintenance of intracellular Ca homeostasis.These results suggest that the blunt sensitivity of TSPO to ischaemic stress may be responsible for the antiarrhythmic effects by CIHH.
Affiliation: Key Laboratory of Arrhythmias, Ministry of Education of China, Shanghai, China.Show MeSH
Related in: MedlinePlus
Mentions: As illustrated in Figure 2A and B, ischaemic VF was positively linked to TSPO activity alterations; specifically, ischaemic VF occurrence accompanied by stepped-up elevation of the protein activity. Of note, TSPO activity was higher in CIHH rats than in normoxic ones under basal conditions, and was preserved during ischaemia (Fig. 2B and C). Further analysis indicated that ischaemia did not modify the TSPO mRNA expression in normoxic rats. However, the level of TSPO expression was higher in CIHH rats than in normoxic ones under basal conditions, and was preserved throughout ischaemia (Fig. 2D). This evidence strongly supports the idea that CIHH blunts or resets the sensitivity of TSPO to ischaemic stress and further contributes to antiarrhythmia.
Affiliation: Key Laboratory of Arrhythmias, Ministry of Education of China, Shanghai, China.