Combined administration of direct dopamine receptor agonists and L-dopa does not interfere with utilization of exogenous L-dopa in rat corpus striatum.
The effect of combined administration of L-dopa with apomorphine or with bromocriptine on rat striatal concentrations of dopamine (DA), dihydroxyphenylacetic (DOPAC) and dopa was investigated. Injections of apomorphine or bromocriptine alone decreased striatal DOPAC levels indicating suppression of DA turnover in nigrostriatal terminals. The dopa-induced elevations in striatal concentrations of DA, DOPAC and dopa were similar among animals injected with L-dopa alone or in combination with apomorphine or bromocriptine. These findings suggest that although direct DA receptor agonists decrease striatal DA turnover, they do not interfere with utilization of exogenous L-dopa in striatum.
D015102:3,4-Dihydroxyphenylacetic Acid / Q000378:metabolism; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D001971:Bromocriptine / Q000494:pharmacology*; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism; D004298:Dopamine / Q000378:metabolism; D007980:Levodopa / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D009115:Muridae; D011954:Receptors, Dopamine / Q000187:drug effects*; D009435:Synaptic Transmission / Q000187:drug effects
D011954:Receptors, Dopamine; D015102:3,4-Dihydroxyphenylacetic Acid; D001971:Bromocriptine; D007980:Levodopa; D001058:Apomorphine; D004298:Dopamine