Linked Life Data

6222267

Source:http://linkedlifedata.com/resource/pubmed/id/6222267

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1983-7-8
pubmed:abstractText
Various functions involving the central nervous system can be manipulated by the sequential administration of p-chlorophenylalanine and 5-hydroxytryptophan, compounds which respectively inhibit and restore the synthesis of 5-hydroxytryptamine in the brain. An involvement of 5-hydroxytryptamine in the control of a particular function has been considered established when the effect of p-chlorophenylalanine on that function can be overcome by treatment with 5-hydroxytryptophan. This assumption is not, however, invariably substantiated when the functional consequences of other methods of depleting 5-hydroxytryptamine are considered; studies on the control of the daily surge of luteinizing hormone in oestrogen-treated ovariectomized rats present such a paradox. The surge can be prevented by p-chlorophenylalanine and restored by 5-hydroxytryptophan. Nevertheless, neurotoxin-induced lesions of the 5-hydroxytryptamine projections from the raphe nuclei are compatible with a normal occurrence of the surge. We have therefore examined the effects of p-chlorophenylalanine and 5-hydroxytryptophan on hypothalamic monoamines in oestrogen-treated ovariectomized rats and find that the drugs respectively suppress and elevate the concentration of adrenaline in addition to that of 5-hydroxytryptamine. Phenylethanolamine N-methyltransferase, the enzyme responsible for converting noradrenaline to adrenaline, is shown to be inhibited in vivo by p-chlorophenylalanine and in vitro by its metabolite, p-chlorophenylethylamine. The reciprocal effects of p-chlorophenylalanine and 5-hydroxytryptophan on the concentration of adrenaline are of particular interest since drugs which inhibit adrenaline synthesis can block the luteinizing hormone surge. It is proposed that when the 5-hydroxytryptophan-reversible effects of treatment with p-chlorophenylalanine are not reproduced by other procedures which deplete 5-hydroxytryptamine, the significant action of these compounds may involve adrenaline.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0306-4522
pubmed:author
pubmed:issnType
Print
pubmed:volume
8
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
583-91
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Possible resolution of a paradox concerning the use of p-chlorophenylalanine and 5-hydroxytryptophan: evidence for a mode of action involving adrenaline in manipulating the surge of luteinizing hormone in rats.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't