Action of apomorphine, bromocriptine and lergotrile on gamma-aminobutyric acid and acetylcholine release in nucleus accumbens and corpus striatum.
The effect of three dopamine agonists, apomorphine, bromocriptine and lergotrile, was tested on the release of gamma-aminobutyric acid, (GABA) and acetylcholine (ACh) from tissue slices of rat nucleus accumbens and striatum. All three agents in vitro caused a dose dependent depression of the K+-evoked release of [14C]-GABA in corpus striatum. This effect was also obtained following in vivo drug application and when endogenous GABA release was determined. A similar depression of GABA release was obtained in the nucleus accumbens. Both dopamine and dibutyryl adenosine-3':5'-cyclic monophosphoric acid inhibited the K+-evoked release of [14C]-GABA in corpus striatum. This inhibitory effect was not reversed by sulpiride. Bromocriptine and lergotrile also depressed the K+-evoked release of [3H]-acetylcholine from tissue slices of corpus striatum but not nucleus accumbens, as has previously been demonstrated for dopamine and apomorphine. In contrast, sulpiride enhanced the release of [3H]-acetylcholine and molindone reversed the apomorphine inhibition of [3H]-acetylcholine release. These results indicate that dopaminergic agents may influence the release of both GABA and ACh in the corpus striatum but only GABA in the nucleus accumbens.
D000109:Acetylcholine / Q000378:metabolism*; D000344:Afferent Pathways / Q000187:drug effects; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001971:Bromocriptine / Q000494:pharmacology*; D003994:Bucladesine / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects*; D046508:Culture Techniques; D004305:Dose-Response Relationship, Drug; D004873:Ergolines / Q000031:analogs & derivatives* / Q000494:pharmacology; D008297:Male; D008972:Molindone / Q000494:pharmacology; D009115:Muridae; D009714:Nucleus Accumbens / Q000187:drug effects*; D011954:Receptors, Dopamine / Q000187:drug effects; D012686:Septal Nuclei / Q000187:drug effects*; D013469:Sulpiride / Q000494:pharmacology; D009435:Synaptic Transmission / Q000187:drug effects; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D004873:Ergolines; D011954:Receptors, Dopamine; D001971:Bromocriptine; D005680:gamma-Aminobutyric Acid; D003994:Bucladesine; D013469:Sulpiride; D001058:Apomorphine; D000109:Acetylcholine; C031875:lergotrile; D008972:Molindone