Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1986-1-21
pubmed:abstractText
The sensitivity of alpha 2-adrenoceptors on 5-hydroxytryptamine (5-HT) nerve endings obtained from rat cerebral cortex was investigated following treatment with the antidepressant drugs desipramine (10 mg/kg/day for 21-28 days) or clorgyline (1 mg/kg/day for 21-28 days). [3H]5-HT (100 nM) was used to load cortical synaptosomes (P2) after experiments with uptake inhibitors confirmed that this concentration of amine ensured exclusive uptake into 5-HT nerve terminals. The sensitivity of K+-stimulated release of [3H]5-HT to alpha 2-adrenoceptor occupancy was assessed in a superfusion system by means of the dose-dependent inhibition of [3H]5-HT release by clonidine. This is blocked by yohimbine (1 microM), which, when administered alone, enhances release, suggesting that endogenous catecholamines released from other synaptosomes act on these alpha 2-heteroreceptors. The effect of addition of citalopram (1 microM) to superfusates suggests that some reuptake of [3H]5-HT occurs during superfusion. Of the tritium released into superfusates during "background" and K+-stimulated release, 17 and 90%, respectively is [3H]5-HT. The attenuation of K+-stimulated release by clonidine is apparently diminished by the chronic clorgyline regimen but not by desipramine. However, clorgyline elevates catecholamine levels, and this might increase endogenous noradrenaline (NA) efflux, which by competition with clonidine could appear to alter alpha 2-adrenoceptor sensitivity. This possibility was investigated by depleting NA with the neurotoxin N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4). These studies showed that the apparent effect of chronic clorgyline on alpha 2-adrenoceptor sensitivity to clonidine was due to competition with increased levels of endogenous NA.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
http://linkedlifedata.com/resource/pubmed/chemical/Antidepressive Agents, http://linkedlifedata.com/resource/pubmed/chemical/Benzylamines, http://linkedlifedata.com/resource/pubmed/chemical/Citalopram, http://linkedlifedata.com/resource/pubmed/chemical/Clonidine, http://linkedlifedata.com/resource/pubmed/chemical/Clorgyline, http://linkedlifedata.com/resource/pubmed/chemical/DSP 4, http://linkedlifedata.com/resource/pubmed/chemical/Desipramine, http://linkedlifedata.com/resource/pubmed/chemical/Hydroxyindoleacetic Acid, http://linkedlifedata.com/resource/pubmed/chemical/Maprotiline, http://linkedlifedata.com/resource/pubmed/chemical/Nomifensine, http://linkedlifedata.com/resource/pubmed/chemical/Potassium, http://linkedlifedata.com/resource/pubmed/chemical/Propylamines, http://linkedlifedata.com/resource/pubmed/chemical/Receptors, Adrenergic, alpha, http://linkedlifedata.com/resource/pubmed/chemical/Serotonin, http://linkedlifedata.com/resource/pubmed/chemical/Yohimbine
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0022-3042
pubmed:author
pubmed:issnType
Print
pubmed:volume
46
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
218-23
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:2415679-Animals, pubmed-meshheading:2415679-Antidepressive Agents, pubmed-meshheading:2415679-Benzylamines, pubmed-meshheading:2415679-Cerebral Cortex, pubmed-meshheading:2415679-Citalopram, pubmed-meshheading:2415679-Clonidine, pubmed-meshheading:2415679-Clorgyline, pubmed-meshheading:2415679-Desipramine, pubmed-meshheading:2415679-Hydroxyindoleacetic Acid, pubmed-meshheading:2415679-Male, pubmed-meshheading:2415679-Maprotiline, pubmed-meshheading:2415679-Nomifensine, pubmed-meshheading:2415679-Potassium, pubmed-meshheading:2415679-Propylamines, pubmed-meshheading:2415679-Rats, pubmed-meshheading:2415679-Rats, Inbred Strains, pubmed-meshheading:2415679-Receptors, Adrenergic, alpha, pubmed-meshheading:2415679-Serotonin, pubmed-meshheading:2415679-Synaptosomes, pubmed-meshheading:2415679-Yohimbine
pubmed:year
1986
pubmed:articleTitle
Studies on the role of alpha 2-adrenoceptors in the control of synaptosomal [3H]5-hydroxytryptamine release: effects of antidepressant drugs.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't