The role of substance P in cerebral edema associated with rat and human infarction and contusion

Abstract

An important influence on the severity of both traumatic brain injury (TBI) and stroke is cerebral edema, but its mechanism is poorly understood. Recent evidence suggests that substance P (SP) plays a role in this edema and that injured SP-containing perivascular nerve fibres are involved. A study which examined tissue obtained from rat models and human post mortem infarct and contusion tissue, demonstrated that in all the examined tissue, perivascular SP-IR was present in astrocytic processes rather than in nerve fibres. This implies that perivascular astrocytic processes might be more important than perivascular nerve fibres in any effect that SP may have on the blood brain barrier in the settings of infarction and contusion.