Acute toxicity of perfluorodecalin emulsion for rabbits

Abstract

The toxicity of injected intravenously to rabbits perfluorodecalin (PFD) emulsion (10% vol/vol) with 4% Proxanol 268 (USSR analog of Pluronic F-68) as a stabilizer was studied. LD 50 of PFD emulsion was approximately 13 ml/kg, corresponding to the data, reported previously[l]. Perfluoro-p-methylcyclohexyl- piperidine (PFMCP) emulsion at a dose 10 ml/kg effectively eliminated the PFD emulsion toxicity while using any mode of injection: simultaneous injection of PFD and PFMCP emulsions; administration of PFMCP emulsion 5–7 days before or 5–12 days after administration of PFD emulsion. Perfluorotripropylamine (PFTPA) emulsion wasn't toxic for rabbits, suggesting that gas embolia couldn't cause animal death under administration of PFD emulsion (P v of PFD and PFTPA are 12 and 20 mm Hg respectively). Rabbits death also couldn't be caused by liver cytochrome P-450 induction and some other membrane effects of PFD, because emulsion of even more lipophilic perfluorooctylbromide(PFOB) wasn't toxic (CST of PFD and PFOB are 22 and 5°C respectively). It is suggested that the cause of rabbit death after administration of PFD emulsion is unstability of the letter in circulatory system, which results in thrombosis of pulmonary capillaries. Freeze-fracture electron microscopy revealed the large dense aggregates of PFD particles in rabbits blood 1–2 days after PFD emulsion injection.