Positron emission tomograghy with [13N]ammonia evidences long-term cerebral hyperperfusion after 2h-transient focal ischemia

► PET with [13N]NH4+ evidenced brain-blood hyperperfusion after experimental stroke. ► Brain hyperperfusion was observed in both infarcted and remote regions. ► [13N]NH4+ is a useful biomarker to monitor hemodynamic changes after ischemia. ► These results may contribute to understand the evolution of cerebral ischemia.