An analysis of the effects of apomorphine and haloperidol on the release of [3H]-dopamine and [3H]-noradrenaline from rabbit brain slices.
The effects of apomorphine and haloperidol on the K+-induced release of [3H]-dopamine from striatal slices and [3H]-noradrenaline from cerebellar slices were examined. Apomorphine (0.01-1 microM) reduced the K+-induced release of [3H]-dopamine from striatal slices, leaving the K+-induced release of [3H]-noradrenaline from cerebellar slices unaffected. A higher concentration (10 microM) of apomorphine increased significantly the K+-induced release of [3H]-noradrenaline from cerebellar slices. Haloperidol (0.01-1 nM) increased the K+-induced release of [3H]-dopamine from striatal slices, leaving the K+-induced release of [3H]-noradrenaline unaffected. Haloperidol in higher concentrations (10-100nM) increased significantly the K+-induced release of [3H]-noradrenaline from cerebellar slices. Both compounds inhibited the uptake of [3H]-dopamine into striatal slices and [3H] noradrenaline into cerebellar slices. In low concentrations both compounds showed selectivity for dopaminergic receptor sites, apomorphine stimulating and haloperidol inhibiting pre-synaptic dopamine receptors. Higher concentrations of these compounds showed a non-selective action.
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001921:Brain / Q000187:drug effects* / Q000378:metabolism; D002531:Cerebellum / Q000187:drug effects; D003342:Corpus Striatum / Q000187:drug effects; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D006220:Haloperidol / Q000494:pharmacology*; D066298:In Vitro Techniques; D008297:Male; D009638:Norepinephrine / Q000378:metabolism*; D011188:Potassium / Q000494:pharmacology; D011817:Rabbits
D006220:Haloperidol; D001058:Apomorphine; D011188:Potassium; D004298:Dopamine; D009638:Norepinephrine