Regional differences in the effect of the combined treatment of WAY 100635 and fluoxetine: an in vivo microdialysis study - PubMed (original) (raw)

. 1996 Dec;354(6):785-90.

doi: 10.1007/BF00166906.

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Regional differences in the effect of the combined treatment of WAY 100635 and fluoxetine: an in vivo microdialysis study

I Malagié et al. Naunyn Schmiedebergs Arch Pharmacol. 1996 Dec.

Abstract

We studied the changes in extracellular serotonin (5-HT) levels in the frontal cortex (FC) and ventral hippocampus (vHi) in conscious rats, induced by the combined administration of a highly selective 5-HT1A receptor antagonist, WAY 100635 (0.1 mg/kg, i.v.), and fluoxetine (1 mg/kg, i.p.), a selective 5-HT reuptake inhibitor (SSRI). In the two brain areas studied, no change in extracellular 5-HT concentrations was observed following fluoxetine administration over the 210 min post-injection period. However, in animals co-administered with [WAY 100635 + fluoxetine], the maximal increase in 5-HT levels in the FC was to 215% of the respective basal value (100%), while no significant change in 5-HT was observed in dialysates from the vHi. Furthermore, the [norfluoxetine]-to-[fluoxetine] ratio in the FC was significantly higher than in the hippocampus as measured in homogenates of animals treated with either fluoxetine alone or a prior administration of WAY 100635. Thus, WAY 100635 made the fluoxetine short-lasting effect apparent in the FC, but not by interfering with pharmacokinetic parameters of fluoxetine. Taken together, our data suggest the possibility, that either 5-HT1A autoreceptor sensitivity or uptake carrier density or higher [metabolite]-to-[parent drug] ratios in the FC than in the hippocampus may be involved in regional specific responses to SSRIs.

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References

    1. Eur J Pharmacol. 1995 Nov 14;286(2):213-7 - PubMed
    1. Brain Res. 1992 Jul 3;584(1-2):322-4 - PubMed
    1. Synapse. 1987;1(1):3-9 - PubMed
    1. J Pharmacol Exp Ther. 1993 Jun;265(3):1319-24 - PubMed
    1. J Neurochem. 1993 Feb;60(2):776-9 - PubMed

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