Cardioprotection via activation of protein kinase C-δ depends on modulation of the reverse mode of the Na+/Ca2+ exchanger

BACKGROUND - Pretreatment with the volatile anesthetic sevoflurane protects cardiomyocytes against subsequent ischemic episodes caused by a protein kinase C (PKC)-δ mediated preconditioning effect. Sevoflurane directly modulates cardiac Ca handling, and because Ca also serves as a mediator in other cardioprotective signaling pathways, possible involvement of the Na/Ca exchanger (NCX) in relation with PKC-δ in sevoflurane-induced cardioprotection was investigated. METHODS AND RESULTS - Isolated right ventricular rat trabeculae were subjected to simulated ischemia and reperfusion (SI/R), consisting of superfusion with hypoxic glucose-free buffer for 40 minutes after rigor development, followed by reperfusion with normoxic glucose containing buffer. Preconditioning with sevoflurane before SI/R improved isometric force development during contractile recovery at 60 minutes after the end of hypoxic superfusion (83±7% [sevo] versus 57±2% [SI/R];n=8; P