Blood–brain barrier, reperfusion injury, and hemorrhagic transformation in acute ischemic stroke

It has been more than a century since Paul Ehrlich, in 1885, and later his student Edwin Goldmann, proposed that a barrier existed between the CNS and the peripheral circulation. 1 While studying the limited permeation of potassium ferrocyanate into the brain in 1900, Lewandowsky coined the term bluthirnschranke, blood-brain barrier (BBB). 1 The BBB is considered the gatekeeper of the CNS, whose main role is to maintain the fragile homeostasis of the brain designed by segregating the CNS from the systemic circulation.