Acute and chronic triptan exposure neither alters rodent cerebral blood flow nor worsens ischemic brain injury. (6th January 2017) - Muzzi, Mirko
Highlights: Acute eletriptan (1 or 10 mg/kg, i.p.) does not affect cerebral blood flow in rat and mouse brain cortex. Acute or chronic eletriptan (1 mg/kg, i.p.) does not worsen ischemic brain injury in mice subjected to MCAo/reperfusion. Chronic eletriptan reduces VIP and PACAP but 5HT1B/D R and CGRP transcripts in mouse brain cortex. Abstract: Although it is still debated whether vasoconstriction underlies migraine resolution by triptans, they are not recommended in patients at cardiovascular risk. However, relationship between stroke incidence and triptan use is unclear, and it is unknown whether acute or chronic use of these drugs worsens ischemic brain injury. To address this issue, we investigated the effect of clinically-relevant doses of the potent cerebral artery vasoconstrictor eletriptan on cerebral blood flow (CBF) and brain infarct volumes, as well as on expression of genes involved in cerebrovascular regulation. We report that acute treatment of rats or mice with eletriptan did not reduce basal CBF, which promptly dropped upon treatment with prazosin or dihydroergotamine. Acute of chronic (1 month) eletriptan also did not affect CBF changes and infarct volumes in mice undergoing brain ischemia/reperfusion. Finally, chronic eletriptan reduced brain mRNAs for PACAP and VIP, leaving unaffected those for 5HT1B/D R and CGRP. No significant transcript changes were found in dura mater. Data suggest that the impact of triptans on cerebral hemodynamic should be re-evaluated, as well as their propensity to increase stroke risk in migraineurs.