Fig. 4. Isoflurane applied directly to mitochondria is not protective against mitochondrial permeability transition pore (mPTP) opening. (  A ) Representative time courses of mPTP opening in mitochondria exposed to isoflurane directly (ISO) and control (C) mitochondria. The concentration of Ca²⁺necessary to open mPTP was comparable in both groups. (  B ) Summary of the effect of ISO on the mPTP opening elicited by Ca²⁺overload. FCCP = carbonylcyanide-p-trifluoromethoxyphenylhydrazone (mitochondrial uncoupler); ISO = isoflurane; ΔΨ^m= mitochondrial membrane potential. Values are means ± SD; n = 7.