AI Article Synopsis
- The study measured how 3H-labelled PAF-acether is distributed and eliminated in seven rabbits after intravenous administration, finding it spread quickly but cleared slowly.
- The main metabolic process is the conversion of PAF-acether to lyso-PAF-acether, with a stable equilibrium ratio of 10% PAF-acether to 90% lyso-PAF-acether seen within 30 minutes.
- A three-compartment model was used to describe the pharmacokinetics of both compounds, but the reacetylation of lyso-PAF-acether back to PAF-acether could not be confirmed despite its theoretical likelihood.
Article Abstract
The blood and plasma kinetics of intravenously administered 3H-labelled PAF-acether were determined in seven rabbits. PAF-acether was rapidly distributed and slowly eliminated. Individual variations were very small. The main route of metabolism involves deacetylation of the PAF-acether into lyso-PAF-acether, leading to an equilibrium between the two molecules (10%/90%). This equilibrium, observed within 30 minutes, was still the same after 6 hours suggesting in vivo reacetylation of lyso-PAF-acether into PAF-acether. However, this could not be verified. After intravenous administration of lyso-PAF-acether in two rabbits, PAF-acether could not be found in any blood sample. The pharmacokinetic behaviour of both PAF-acether and lyso-PAF-acether can be described by a three-compartment model.
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| http://dx.doi.org/10.1007/BF01966786 | DOI Listing |
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