title: The effect of blocking dopamine release on synthesis rate of dopamine in the striatum of the rat.
abstract: Two experiments were carried out in rats to investigate the mechanisms by which dopamine (DA) synthesis is regulated. First, a unilateral lesion was made in the substantia nigra, thus interrupting the nervous impulse flow of the nigro-striatal pathway. Secondly, the release of DA in the striatum was blocked by means of 1-hydroxy-3-amino-pyrrolidone-2 (HA-966). In both experiments the synthesis rate of DA was accelerated as was shown by analysing the time course of the specific activity of striatal DA after an i.v. injection of 3,5-3H-tyrosine. Furthermore the influence of apomorphine on the rate of DA synthesis, accelerated by HA-966 or by lesion, was investigated. Apomorphine appeared to block the increase of DA synthesis. The results are discussed in the light of a transsynaptic feedback mechanism.
mesh_terms: D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D003342:Corpus Striatum / Q000378:metabolism* / Q000502:physiology; D004298:Dopamine / Q000096:biosynthesis / Q000378:metabolism*; D005246:Feedback; D006220:Haloperidol / Q000494:pharmacology; D007700:Kinetics; D008297:Male; D009434:Neural Pathways / Q000502:physiology; D011760:Pyrrolidinones / Q000494:pharmacology; D051381:Rats; D013378:Substantia Nigra / Q000502:physiology; D009435:Synaptic Transmission / Q000187:drug effects; D013997:Time Factors; D014443:Tyrosine / Q000378:metabolism
chemical_list: D011760:Pyrrolidinones; D014443:Tyrosine; C001369:1-hydroxy-3-amino-2-pyrrolidone; D006220:Haloperidol; D001058:Apomorphine; D004298:Dopamine