The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Biotransformation of 1,1,1,3,3-Pentafluoropropane (HFC-245fa).

1,1,1,3,3-Pentafluoropropane (HFC-245fa) is being developed as a CFC substitute. 1,1,1,3,3-Pentafluoropropane has a low potential for toxicity: the only remarkable toxic effect seen in rats after inhalation exposure to 1,1,1,3,3-pentafluoropropane in concentrations of up to 50,000 ppm for 90 days was an increased incidence of diffuse myocarditis. To elucidate the possible role of biotransformation in 1,1,1,3,3-pentafluoropropane-induced cardiotoxicity, the biotransformation of 1,1,1,3,3-pentafluoropropane was investigated in rats after inhalation exposure and in rat and human liver microsomes. Male and female rats were exposed by inhalation to 50 000, 10 000, and 2000 ppm 1,1,1,3,3-pentafluoropropane for 6 h, urine was collected for 72 h, and metabolites excreted were identified by 19F NMR spectroscopy and quantified by GC/MS. Trifluoroacetic acid and inorganic fluoride were identified as major urinary metabolites of 1,1,1,3,3-pentafluoropropane; 3,3,3-trifluoropropanoic acid and 1,1,1,3,3-pentafluoropropane-2-ol were minor metabolites. The extent of 1,1,1,3,3-pentafluoropropane biotransformation after inhalation was dependent on exposure concentrations. Neither 3,3,3-trifluoropropanoic acid nor 3,3,3-trifluoropyruvic acid were metabolized to trifluoroacetic acid in vitro or in rats. In rat and human liver microsomes, 1,1,1,3,3-pentafluoropropane was biotransformed by a cytochrome P450-dependent reaction to trifluoroacetic acid and 3,3,3-trifluoropropanoic acid. Rates of trifluoroacetic acid formation were 99.2 +/- 20.5 pmol (mg of protein)(-)(1) min(-)(1) and of 3,3,3-trifluoropropanoic acid formation were 17.5 +/- 4.0 pmol (mg of protein)(-)(1) min(-)(1) in liver microsomes from male rats. In human liver microsomes, rates of trifluoroacetic acid formation ranged from 0 to 11.6 pmol (mg of protein)(-)(1) min(-)(1), and rates of 3,3,3-trifluoropropanoic acid formation ranged from 0.7 to 7.6 pmol (mg of protein)(-)(1) min(-)(1). The results show that 1,1,1,3,3-pentafluoropropane is metabolized at low rates in vivo and in vitro. The toxic effects of 1,1,1,3,3-pentafluoropropane may be associated with the formation of the minor metabolite 3,3,3-trifluoropropanoic acid, which is highly toxic in rats.[1]

References

  1. Biotransformation of 1,1,1,3,3-Pentafluoropropane (HFC-245fa). Bayer, T., Amberg, A., Bertermann, R., Rusch, G.M., Anders, M.W., Dekant, W. Chem. Res. Toxicol. (2002) [Pubmed]
 
WikiGenes - Universities