Continuous Glibenclamide Prevents Hemorrhagic Transformation in a Rodent Model of Severe Ischemia-Reperfusion.

BACKGROUND Endovascular thrombectomy (EVT) is highly effective but may also lead to hemorrhagic transformation (HT) and edema, which may be more pronounced in severe ischemia. We sought to determine whether glibenclamide can attenuate HT and edema in a severe ischemia-reperfusion model that reflects EVT. METHODS Using a transient middle cerebral artery occlusion (tMCAo) rodent model of stroke, we studied two rat cohorts, one without rt-PA and a second cohort treated with rt-PA. Glibenclamide or vehicle control was administered as an intravenous bolus at reperfusion, followed by continuous subcutaneous administration with an osmotic pump. RESULTS Compared to vehicle control, glibenclamide improved neurological outcome (median 7, interquartile range [IQR 6-8] vs. control median 6 [IQR 0-6], p = 0.025), reduced stroke volume (323 ± 42 vs. 484 ± 60 mm3, p < 0.01), swelling volume (10 ± 4 vs. 28 ± 7%, p < 0.01) and water content (84 ± 1 vs. 85 ± 1%, p < 0.05). Glibenclamide administration also reduced HT based on ECASS criteria, densitometry (0.94 ± 0.1 vs. 1.15 ± 0.2, p < 0.01), and quantitative hemoglobin concentration (2.7 ± 1.5 vs. 6.2 ± 4.6 uL, p = 0.011). In the second cohort with rt-PA coadministration, concordant effects on HT were observed with glibenclamide. CONCLUSIONS Taken together, these studies demonstrated that glibenclamide reduced the amount of edema and HT after severe ischemia. This study suggests that co-administration of glibenclamide may be worth further study in severe stroke patients treated with EVT with or without IV rt-PA.