Linked Life Data

6707946

Source:http://linkedlifedata.com/resource/pubmed/id/6707946

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1984-5-23
pubmed:abstractText
This study tested the hypothesis that phencyclidine (PCP) is an indirect dopamine (DA) agonist in the caudate nucleus. Single caudate neurons in rats anesthetized with urethane were recorded extracellularly with multibarrel micropipettes. Effects of drug solutions, applied by pressure microejection, were measured as changes in spontaneous and evoked neuronal activity. Caudate neurons were classified according to their latency-to-discharge in response to supramaximal cortical stimulation. PCP inhibited the spontaneous activity of 92% of neurons with latencies less than 13 msec, while DA inhibited 87%. Both drugs inhibited evoked activity significantly less than spontaneous activity (P less than .01). Neurons with latencies greater than 13 msec were excited by DA significantly more often (45%) than by PCP (13%; P less than .05). Receptor stereospecificity is suggested by the finding that the (+)-isomer of the 3-methyl piperidine derivative of PCP was significantly more potent than the (-)-isomer for inhibition of spontaneous activity. Mg++, which blocks presynaptic release of neurotransmitter, significantly antagonized inhibitory effects of PCP on spontaneous activity, which suggests a presynaptic effect of PCP. DA, which acts postsynaptically, was much less affected by Mg++. The potency of PCP was significantly less in rats treated with reserpine or 6-hydroxydopamine than in control rats, suggesting the endogenous DA is required for the action of PCP. Fluphenazine and (+)-butaclamol, potent DA-receptor antagonists, blocked the effect of PCP, but (-)-butaclamol did not. These results support the hypothesis that PCP facilitates release and/or inhibits reuptake of DA in nerve terminals and thereby acts as an indirect DA agonist in the caudate. However, there may be a subpopulation of caudate neurons in which PCP acts by a nondopaminergic mechanism.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
229
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
321-32
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1984
pubmed:articleTitle
Presynaptic dopaminergic activity of phencyclidine in rat caudate.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.