Abstract
Background/Objectives: In recent years, it has been suggested that sedatives may cause brain damage. One possible mechanism is interference with oxidative phosphorylation of brain mitochondria, but much remains unknown. In this study, we focused on dexmedetomidine, midazolam, and propofol, essential sedatives in anesthesia and intensive care, and aimed to understand the effects of these drugs on mouse brain mitochondria. Methods: We measured changes in mitochondrial respiratory capacity and swelling rate upon exposure to these sedatives in a wide concentration range. For the sedative that demonstrated impaired mitochondrial function we explored the possible involvement of mitochondrial permeability transition pore opening using brain mitochondria from cyclophilin D knockout (CypD KO) mice and detected cytochrome c (cyt c) release by Western blot. Results: Of the three sedatives, only high concentrations of propofol exhibited reduced respiratory capacity and mitochondrial swelling, toxicity which was not prevented by CypD KO. Furthermore, propofol did not induce cyt c release. Conclusions: These results suggest that propofol-induced brain mitochondrial dysfunction is a mechanism independent of mPTP opening.