Of　all　the　aerobic　respiration　by-products,　cytotoxic　superoxide　derived　from　mitochondrial-leaked　electrons,　is　the　only　one　known　to　be　disposed　of　intracellularly.　Is　this　fate　the　only　destiny　for　mitochondrial-leaked　electrons?　When　Cynomolgus　monkeys　were　injected　intravenously　with　reactive　oxygen　species　(ROS)　indicators,　the　connective　tissues　of　dura　mater,　facial　fascia,　pericardium,　linea　alba,　dorsa　fascia　and　other　body　parts,　emitted　specific　and　intense　fluorescent　signals.　Moreover,　the　fluorescent　signals　along　the　linea　alba　of　SD　rats,　did　not　result　from　the　local　presence　of　ROS　but　from　the　interaction　of　ROS　indicators　with　electrons　flowing　through　this　tissue.　Furthermore,　the　electrons　travelling　along　the　linea　alba　of　mice　were　revealed　to　originate　from　mitochondria.　These　data　suggest　that　mitochondrial-leaked　electrons　may　be　transported　extracellularly　to　a　hitherto　undescribed　system　of　connective　tissues,　which　is　pervasively　networked,　electrically　conductive　and　metabolically　related.