Enhanced vasoconstrictor effect of endothelin in cerebral arteries from rats with subarachnoid haemorrhage.

The contractile response to endothelin has been examined in cerebral arteries from rats subjected to a prior subarachnoid haemorrhage (SAH) and compared with saline-injected controls. Endothelin elicited concentration-dependent contractions of rat basilar artery segments. The endothelin-induced contractions were much stronger in the SAH compared to control animals, which suggests a role in the pathophysiology of cerebral vasospasm.