This study examined the effects of phosphodiesterase 5 (PDE5) inhibition using sildenafil on cerebral vasospasm and functional recovery in a mouse model of subarachnoid hemorrhage (SAH). The researchers found that sildenafil treatment significantly reduced cerebral vasospasm in the middle cerebral artery compared to vehicle treatment. Mice treated with sildenafil also showed markedly improved neurological function based on tests of motor skills and coordination compared to vehicle-treated mice. The results suggest that PDE5 inhibition may be a promising new therapeutic approach for ameliorating cerebral vasospasm and improving outcomes after SAH.