A/A-->B) ratio = 5.1] with high passive membrane permeability (P(app) = 64-170 nm/s); however, GV196771 was not an in vitro Mdr1a substrate (B-->A/A-->B ratio = 1.9; no effect of GF120918 on efflux ratio). The role of Pgp and Bcrp on the systemic exposure of GV196771 was assessed by pretreatment of wild-type and Pgp-deficient mdr1a/1b(-/-) mice with a single oral dose of GF120918 (50 mg/kg; a dual Pgp and Bcrp inhibitor) or vehicle (0.5% hydroxypropylmethylcellulose and 1% Tween 80) 2 h before administration of a single oral dose of GV196771 (2 mg/kg). Compared with wild-type animals, the GV196771 area under the plasma concentration-time curve [AUC((0-->6 h))] increased 6.2-fold in Pgp-deficient mice, 10.3-fold in GF120918-pretreated wild-type mice, and 16.4-fold in GF120918-pretreated Pgp-deficient mice. C(max) values changed in parallel with the AUC((0-->6 h)) values; however, t(max) remained relatively unchanged. This study supports a role for Pgp and Bcrp in attenuating the systemic exposure of GV196771 in mice and demonstrates that two ABC efflux transporters can have nonredundant roles in attenuating the disposition of a compound.
-->
| Autor: |
W, Polli Joseph, M, Baughman Todd, E, Humphreys Joan, H, Jordan Kelly, L, Mote Angela, O, Webster Lindsey, J, Barnaby Robert, Giovanni, Vitulli, Luigina, Bertolotti, D, Read Kevin, J, Serabjit-Singh Cosette |
| Zdroj: |
Drug Metabolism and Disposition; July 2004, Vol. 32 Issue: 7 p722-6, 5p |
| Abstrakt: |
GV196771 [E-4,6-dichloro-3-(2-oxo-1-phenyl-pyrrolidin-3-glydenemethyl)-1H-indole-2 carboxylic acid] is a potent antagonist of the modulatory glycine site of the N-methyl-d-aspartate receptor. GV196771 has low oral bioavailability (<10%) and plasma clearance ( approximately 2 ml/min/kg) in rats. P-Glycoprotein (Pgp) and breast cancer resistance protein (Bcrp) are ATP-binding cassette (ABC) transporters that limit the oral absorption of drugs and dietary constituents. The objective of this work was to assess the involvement of Pgp and/or Bcrp on the systemic exposure of GV196771 in mice. In vitro, GV196771 was a Bcrp substrate [basolateral-to-apical/apical-to-basolateral (B-->A/A-->B) ratio = 5.1] with high passive membrane permeability (P(app) = 64-170 nm/s); however, GV196771 was not an in vitro Mdr1a substrate (B-->A/A-->B ratio = 1.9; no effect of GF120918 on efflux ratio). The role of Pgp and Bcrp on the systemic exposure of GV196771 was assessed by pretreatment of wild-type and Pgp-deficient mdr1a/1b(-/-) mice with a single oral dose of GF120918 (50 mg/kg; a dual Pgp and Bcrp inhibitor) or vehicle (0.5% hydroxypropylmethylcellulose and 1% Tween 80) 2 h before administration of a single oral dose of GV196771 (2 mg/kg). Compared with wild-type animals, the GV196771 area under the plasma concentration-time curve [AUC((0-->6 h))] increased 6.2-fold in Pgp-deficient mice, 10.3-fold in GF120918-pretreated wild-type mice, and 16.4-fold in GF120918-pretreated Pgp-deficient mice. C(max) values changed in parallel with the AUC((0-->6 h)) values; however, t(max) remained relatively unchanged. This study supports a role for Pgp and Bcrp in attenuating the systemic exposure of GV196771 in mice and demonstrates that two ABC efflux transporters can have nonredundant roles in attenuating the disposition of a compound. |
| Databáze: |
Supplemental Index |
| Externí odkaz: |
|
