Biocompatibility studies with perfluorochemical oxygen carriers.

The effects of injecting either a novel perfluorodecalin (FDC)-based emulsion or various perfluorochemical (PFC) oils on liver cytochromes P-450 (P-450) and aryl esterase (LAE) enzymes in male rats have been studied. Mean P-450 concentration increased (P less than 0.05) following injection of the novel emulsion or FDC. In contrast, LAE increased in response to injection of FDC (P less than 0.05) and the C-16 oil, perfluoroperhydrofluoranthrene (P less than 0.01), added to stabilize the emulsion. No corresponding changes in either P-450 or LAE occurred in rats injected with either perfluorotripropylamine, perfluorotributylamine or perfluorooctylbromide. The "sleeping time" of animals injected with the pentobarbital-based anaesthetic, Equithesin, following pretreatment with the novel emulsion was lower (P less than 0.05) than in saline-injected controls. The results are discussed in relation to the effects of PFCs on liver metabolic functions.

Effects of emulsified perfluorochemicals on liver aryl esterase in rats.

1. The effects of intravenous (i.v.) injection of various perfluorochemical (PFC) emulsions have been studied separately in male and female rats. 2. Injection of 10 ml/kg body weight of either Fluosol-DA 20% (F-DA) or a novel perfluorodecalin emulsion containing a C-16 oil additive in male rats increased liver weight up to 7 days later; no corresponding change occurred in response to injection of Oxypherol (FC-43). 3. Liver weight was also increased in female rats at 72 hr after injection of the novel emulsion but this was less pronounced than in males; liver weight in female rats was unchanged in response to injection of either F-DA or FC-43. 4. Mean liver aryl esterase activity in male rats was increased 2- to 3-fold (P less than 0.05) at 7 days after injection of the novel emulsion. No significant alterations in aryl esterase activity occurred in response to injection of either F-DA or FC-43, although in both cases there was a trend towards increased activity. 5. Liver aryl esterase activity in female rats was significantly (P less than 0.05) decreased at 72 hr following FC-43 injection with similar, but much less pronounced, changes occurring in response to injection of F-DA and the novel emulsion. 6. These results show that injection of a single low dose of emulsified PFCs into rats can alter hepatic microsomal aryl esterase activity but the response is highly variable, depending on composition of emulsion injected and sex of recipient.

Oxygen-transport fluid based on perfluorochemicals: effects on liver biochemistry.

The effects of (1) i.v. injection of various perfluorochemical (PFC) emulsions, (2) different fractions of the non-ionic poloxamer surfactant, Pluronic F-68, or (3) i.p. injection of component PFC oils have been studied separately in male and female rats. Injection of 10 ml/kg body wt of either Fluosol-DA 20% (F-DA) or a novel perfluorodecalin emulsion containing a C-16 oil additive in male rats increased liver weight up to 7 days later; no corresponding effect occurred in response to injection of Oxypherol (FC-43). Liver weight was also increased in female rats at 72 hr after injection of the novel emulsion but this was less pronounced than in males; liver weight in female rats was unchanged in response to injection of either F-DA or FC-43 but was 12% greater at 72 hr after injection of FDC oil. Mean liver microsomal cytochromes P-450 concentrations in male rats were increased 2-3 fold at 72 hr after injection of either FDC, F-DA or the novel emulsion; a less pronounced increase was also seen at 7 days in animals receiving the novel emulsion. No significant alterations in cytochromes activity occurred in response to injection of FTPA, FTBA, the C-16 oil, FC-43 or either commercial grade or purified pluronic solution. Liver cytochromes P-450 concentrations in female rats were unaffected by any of the experimental treatments.

Perfluorochemicals and photodynamic therapy in mice.

The effects of pre-treatment with a novel PFC emulsion on PDT-induced tumor necrosis have been studied in mice. Injection of emulsion either 2.5 hr or 24 hr before PDT did not affect the depth of tumour necrosis. However, pre-treatment with the emulsion appeared to protect skin against photodynamic damage although the mechanism(s) and active principle(s) involved were not identified. These results suggest that there may be specific advantages in using emulsified PFCs in conjunction with PDT which may be independent of changes in tumour oxygenation.

Effects of emulsified perfluorochemicals on liver cytochromes P-450 in rats.

1. The effects of intravenous (i.v.) injection of various perfluorochemical (PFC) emulsions or different fractions of the non-ionic poloxamer surfactant, Pluronic F-68, have been studied separately in male and female rats. 2. Injection of 10 ml/kg body wt of either Fluosol-DA 20% (F-DA) or a novel perfluorodecalin emulsion containing a C-16 oil additive in male rats increased liver weight up to 7 days later; no corresponding effect occurred in response to injection of Oxypherol (FC-43). 3. Liver weight was also increased in female rats at 72 hr after injection of the novel emulsion but this was less pronounced than in males; liver weight in female rats was unchanged in response to injection of either F-DA or FC-43. 4. Mean liver microsomal cytochromes P-450 concentrations in male rats were increased 2-3 fold at 72 hr after injection of either F-DA or the novel emulsion with a less pronounced increase also seen at 7 days in animals receiving the novel emulsion. No significant alterations in cytochrome concentration occurred in response to injection of FC-43 or either commercial grade or purified pluronic solution. 5. Liver cytochromes P-450 concentrations in female rats were unaffected by any of the experimental treatments. 6. These results show that injection of a single low dose of emulsified PFCs into male rats can increase hepatic microsomal cytochromes P-450 concentration but the response is highly variable, depending on composition of emulsion injected.