Dipyridamole Treatment Prior to Stroke Onset: Examining Post-stroke Cerebral Circulation and Outcome in Rabbits.

Clinical observations have indicated that secondary treatment with dipyridamole (DIP) may ameliorate stroke severity. The purpose of this study was to explore the effect of pre-stroke DIP treatment on stroke outcome in a rabbit model of embolic occlusion. Twenty male New Zealand white rabbits were randomly selected for intravenous treatment with DIP (n = 10) or saline (n = 10) for 7 days prior to an embolic cerebral occlusion by an autologous blood clot. Multiple computed tomography perfusion scans were acquired out to 28 days post-stroke to map cerebrohemodynamics, in conjunction with neurological assessments and histopathology. The DIP-treated group fared better than the saline group on several accounts: 66% of them survived to 28 days, whilst saline animals all had to be euthanized by day 7 due to severe neurological deficits. They presented with significantly more viable tissue in the ischemic hemisphere as well as fewer neurological deficits on days 4 and 7. Furthermore, DIP-treated animals exhibited improved cerebrohemodynamics by 24 h and had less incidence of haemorrhage within their infarcted regions (p < 0.05). DIP treatment prior to stroke onset can significantly improve neurological outcome, cerebral hemodynamics, and final infarct volume.