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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
3
|
| pubmed:dateCreated |
1985-1-18
|
| pubmed:abstractText |
The uptake of [3H]choline and its conversion to [3H]acetylcholine were investigated in term human placental tissue in vitro. Although the net uptake of [3H]choline increased throughout a 45 min incubation period, intracellular [3H]choline levels reach a plateau after 2 min. There was a constant increase in [3H]acetylcholine levels throughout the incubation period. After 45 min, 36.5 per cent of the total intracellular tritium was recovered as acetylcholine by high-voltage electrophoresis. The effects of the choline acetyltransferase inhibitors, 2-benzoylethyltrimethyl-ammonium chloride (BETA) and 4-naphthylvinyl pyridine (NVP), and an inhibitor of choline uptake, hemicholinium-3 (HC-3), were also investigated for their influence on the uptake and metabolism of [3H]choline. A significant depression in both [3H]choline uptake and [3H]acetylcholine synthesis could be demonstrated with all three compounds, although with somewhat different time courses and activities. An analysis of the accumulation of [3H]acetylcholine in relation to the uptake and intracellular levels of [3H]choline as well as the patterns of inhibition produced by the inhibitors indicates that, unlike nervous tissue, the rate-limiting step in the synthesis of acetylcholine in human placental tissue is the transacetylation reaction catalysed by choline acetyltransferase.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical | |
| pubmed:status |
MEDLINE
|
| pubmed:issn |
0143-4004
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:volume |
5
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
261-70
|
| pubmed:dateRevised |
2004-11-17
|
| pubmed:meshHeading | |
| pubmed:articleTitle |
Investigation of the rate-limiting step in the synthesis of acetylcholine by the human placenta.
|
| pubmed:publicationType |
Journal Article
|