Phenytoin transfer across the in situ perfused rat term placenta
Language English Country Germany Media print
Document type Comparative Study, Journal Article, Research Support, Non-U.S. Gov't
PubMed
9399343
Knihovny.cz E-resources
- MeSH
- Analgesics pharmacokinetics MeSH
- Anticonvulsants pharmacokinetics MeSH
- Chemical Phenomena MeSH
- Antipyrine pharmacokinetics MeSH
- Phenytoin pharmacokinetics MeSH
- Chemistry, Physical MeSH
- Blood Proteins metabolism MeSH
- Rats MeSH
- Perfusion MeSH
- Placenta metabolism MeSH
- Rats, Wistar MeSH
- Pregnancy MeSH
- Protein Binding MeSH
- Chromatography, High Pressure Liquid MeSH
- Animals MeSH
- Check Tag
- Rats MeSH
- Pregnancy MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Comparative Study MeSH
- Names of Substances
- Analgesics MeSH
- Anticonvulsants MeSH
- Antipyrine MeSH
- Phenytoin MeSH
- Blood Proteins MeSH
Transfer of phenytoin (PHT) across the rat term placenta perfused in situ was investigated and compared with that of antipyrine (AP) as a marker of passive diffusion. PHT was shown to cross the placenta with similar kinetics as AP did. Both the first order transfer constant (ktr = 0.070 min-1) and the first order equilibration constant (keq = 0.027 min-1) of PHT were comparable to those of AP (ktr = 0.046 min-1, keq = 0.022 min-1). Similarly, there were significant differences between PHT and AP in the foeto-maternal concentration ratio at equilibrium (FMCReq = 1.01 and 1.09, respectively). The present data indicate that the transfer of PHT through the rat placenta is governed by the same principles as that of AP, i.e. by the mechanism of passive diffusion. Surprisingly, maternal plasma protein binding of PHT (60.5%) did not seem to influence either its rate of transfer or its eventual foeto-maternal concentration ratio.
