Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1995-3-16
pubmed:abstractText
TIQs are thought to be formed by condensation between dopamine and certain metabolites of ethanol, organic solvents and anesthetic gases. Described here are experiments aimed at evaluating TIQs interference with catecholamine synthesis. Rat adrenal pheochromocytoma (PC12) cell lysates were exposed to benzyl-TIQ and phenyl-TIQ. The activities of tyrosine hydroxylase (TH) and dopamine beta-hydroxylase (DBH) were measured by HPLC-based methods following exposure to variable concentrations of TIQs. The effects of TIQs on DBH activity were also assessed in human serum. Dixon plot analyses revealed that TIQs act on TH as competitive inhibitors with different affinity. Ki for benzyl- and phenyl-TIQ were 5 and 3 microM respectively. DBH activity in serum exposed to benzyl- and phenyl-TIQ ranging from 0.2 to 20 microM rose respectively by 12.5% to 58% for benzyl- and by 7.8% to 26% for phenyl-TIQ. Such TIQs interferences with catecholamine metabolism seem to account for dopamine (DA) depletion observed in parallel in vitro experiments on PC12 cells. The dose-dependent inhibition of TH and the increased activity of DBH together with the relatively low effective doses of TIQs suggest this mechanism as a possible explanation of the selective toxicity of styrene and other solvents to dopaminergic systems observed in rabbits following experimental exposure and suspected to occur in occupationally-exposed workers.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0161-813X
pubmed:author
pubmed:issnType
Print
pubmed:volume
15
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
765-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Multiple interferences on catecholamine metabolism by tetrahydroisoquinolines (TIQs).
pubmed:affiliation
Laboratory of Industrial Toxicology, University of Parma, Italy.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't