Progress in Dodecafluoropentane Emulsion as a Neuroprotective Agent in a Rabbit Stroke Model

Dodecafluoropentane emulsion (DDFPe) in 250 nm nanodroplets seems to swell modestly to accept and carry large amounts of oxygen in the body at >29 °C. Small particle size allows oxygen delivery even into hypoxic tissue unreachable by erythrocytes. Using permanent cerebral embolic occlusion in rabbits, we assessed DDFPe dose response as a neuroprotectant at 7 and 24 h post-embolization without lysis of arterial obstructions and investigated blood pharmacokinetics. New Zealand White rabbits (N?=?56) received cerebral angiography and embolic spheres (diameter?=?700–900 μm) occluded middle and/or anterior cerebral arteries. Intravenous DDFPe dosing (2 %?w/v emulsion) began at 60 min and repeated every 90 min until sacrifice at 7 or 24 h post-embolization. Seven-hour groups: (1) control (embolized without treatment, N?=?6), and DDFPe treatment: (2) 0.1 ml/kg (N?=?7), (3) 0.3 ml/kg (N?=?9), (4) 0.6 ml/kg (N?=?8). Twenty-four-hour groups: (5) control (N?=?16), and DDFPe treatment: (6) 0.1 ml/kg (N?=?10). Infarcts as percent of total brain volume were determined using vital stains on brain sections. Other alert normal rabbits (N?=?8) received IV doses followed by rapid arterial blood sampling and GC-MS analysis. Percent infarct volume means significantly decreased for all DDFPe-treated groups compared with controls, p?=?<0.004 to <0.03. Blood DDFP (gas) half-life was 1.45?±?0.17 min with R?=?0.958. Mean blood clearance was 78.5?±?24.9 ml/min/kg (mean?±?SE). Intravenous DDFPe decreases ischemic stroke infarct volumes. Blood half-life values are very short. The much longer therapeutic effect, >90 min, suggests multiple compartments. Lowest effective dose and maximum effective therapy duration are not yet defined. Rapid development is warranted.