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The CGP7930 analogue 2,6-di-tert-butyl-4-(3-hydroxy-2-spiropentylpropyl)-phenol (BSPP) potentiates baclofen action at GABAB autoreceptors

School of Dentistry, The University of Adelaide, Australia.
Clinical and Experimental Pharmacology and Physiology (Impact Factor: 2.41). 05/2008; 35(9):1113-5. DOI: 10.1111/j.1440-1681.2008.04948.x
Source: PubMed

ABSTRACT The pharmacological actions of 2,6-di-tert-butyl-4-(3-hydroxy-2-spiropentylpropyl)-phenol (BSPP), a putative presynaptic GABA(B) receptor modulator, were examined in electrically stimulated rat neocortical brain slices preloaded with [3H]-GABA or [3H]-glutamic acid. At 10 mmol/L, BSPP inhibited the release of [3H]-GABA in the presence of baclofen, but not that of [3H]-glutamic acid. This effect was sensitive to the GABA(B) receptor antagonist (+)-(S)-5,5-dimethylmorpholinyl-2-acetic acid (Sch 50911). Alone, BSPP had no effect on the release of [3H]-GABA or [3H]-glutamic acid. It is concluded that BSPP selectively potentiates the action of baclofen at GABA(B) autoreceptors, but not heteroreceptors and may be a useful ligand to discriminate between presynaptic GABA(B) receptor subtypes.

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    • "Based on the results of the present experiments , it is tempting to speculate that the pharmacological properties of these receptor populations differ as well. Differential enhancement of GABA B receptor populations by positive modulators has been shown in vitro: presynaptic GABA B autoreceptors seem to be sensitive to CGP7930 and the CGP7930 analog BSPP, whereas presynaptic GABA B heteroreceptors are not (Chen et al., 2006; Parker et al., 2008). "
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