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Published on: May 24, 2024
Thrombin-induced cerebral hemorrhage: role of protease-activated receptor-1
Yingying Cheng1, Guohua Xi, Hang Jin
1Department of Neurosurgery, University of Michigan, 109 Zina Pitcher Place, Ann Arbor, MI, 48109-2200, USA.
Abstract:
Thrombin causes blood-brain barrier disruption, and this study examined whether thrombin can cause brain hemorrhage through protease-activated receptor-1 (PAR-1). Male wild type and PAR-1 knockout mice had an intracerebral injection of thrombin or saline. Mice then underwent serial T2 magnetic resonance imaging and were euthanized for brain hemoglobin, iron, and interleukin-1β measurements. Thrombin caused massive T2 lesions and brain hemorrhage in wild type mice. These effects were markedly reduced in PAR-1 knockout mice. Thrombin also increased brain interleukin-1β, and this was absent in PAR-1 knockout mice. In conclusion, thrombin increases interleukin-1β levels and induces intracerebral hemorrhage through PAR-1 activation.
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