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. 1993 Jul;36(1):71–74. doi: 10.1111/j.1365-2125.1993.tb05895.x

Peripheral benzodiazepine receptors in platelets of epileptic patients.

J G Larkin 1, P J McKee 1, G G Thompson 1, M J Brodie 1
PMCID: PMC1364558  PMID: 8396957

Abstract

Tolerance to the anticonvulsant effect of benzodiazepines is likely to involve changes at the central benzodiazepine-GABA receptor complex. Peripheral benzodiazepine receptors (pBZRs), which can be measured in platelets, may also be involved. Using a binding assay with [3H]-PK 11195 as radioligand, pBZRs were assayed in platelets of patients taking a variety of antiepileptic drugs (AEDs). Comparisons were made with untreated patients. pBZR receptor density (mean +/- s.e. mean) was increased vs controls (8083 +/- 557 fmol mg-1 protein) in the platelets of patients taking a polypharmacy regime including the benzodiazepine clobazam (12661 +/- 1011 fmol mg-1 protein, P < 0.005) and also in those receiving sodium valproate as monotherapy (15003 +/- 1756 fmol mg-1 protein, P < 0.01). The significance of these findings is unclear, but the use of a specific pBZR antagonist may be a promising avenue for investigating the mechanism of BZ tolerance and its prevention.

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Selected References

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