Gender and the injured brain.

Ischemic brain injury is increasingly recognized as progressing through non-identical mechanisms in the male vs female brain. It is increasingly accepted that women are protected from cerebrovascular disease relative to men even beyond their menopausal years, and that young boys have higher stroke rates than do girls. The biological basis for this sexual dimorphism in epidemiology of ischemic brain injury, and less clearly in its outcome, is only partially known. However, both hormone-dependent and hormone-independent factors are likely involved, the latter of which is emphasized in this chapter. Understanding the molecular and cell-based mechanisms underlying sex differences in ischemic brain injury is an important step toward designing more effective therapeutic interventions and molecular targets in stroke.