(+)- and (-)-3-PPP exhibit different intrinsic activity at striatal dopamine autoreceptors controlling dopamine synthesis.
Both enantiomers of the dopamine analogue 3-(3-hydroxyphenyl)-N-n-propylpiperidine (3-PPP; 0.5-32 mg/kg s.c.) dose dependently reduced the increase in striatal dopamine (DA) synthesis rate produced by gamma-butyrolactone (GBL). Whereas (+)-3-PPP completely prevented the action of GBL, (-)-3-PPP was only partially effective. In addition, (-)-3-PPP partially antagonised the inhibitory action of apomorphine on the GBL-induced increase in DA synthesis rate. These findings suggest that (+)- and (-)-3-PPP act as full and partial agonists respectively, at striatal DA autoreceptors controlling DA synthesis.
D015107:4-Butyrolactone / Q000494:pharmacology; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism*; D004298:Dopamine / Q000096:biosynthesis*; D007536:Isomerism; D008297:Male; D010880:Piperidines / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000187:drug effects*; D017981:Receptors, Neurotransmitter / Q000187:drug effects
D010880:Piperidines; D011954:Receptors, Dopamine; D017981:Receptors, Neurotransmitter; C026539:preclamol; D001058:Apomorphine; D015107:4-Butyrolactone; D004298:Dopamine