Linked Life Data

8038178

Source:http://linkedlifedata.com/resource/pubmed/id/8038178

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1994-8-19
pubmed:abstractText
Taurine, a beta-amino acid, plays an important role as a neuromodulator and is necessary for the normal development of the brain. Since de novo synthesis of taurine in the brain is minimal and in vivo studies suggest that taurine does not cross the blood-brain barrier, we examined whether the choroid plexus, the blood-cerebrospinal fluid barrier, plays a role in taurine transport in the central nervous system. The uptake of [3H]taurine into ATP-depleted choroid plexus from rabbit was substantially greater in the presence of an inwardly directed Na+ gradient, whereas in the absence of a Na+ gradient taurine accumulation was negligible. A transient inside-negative potential gradient enhanced the Na(+)-driven uptake of taurine into the tissue slices, suggesting that the transport process is electrogenic. Na(+)-driven taurine uptake was saturable with an estimated Vmax of 111 +/- 20.2 nmol/g per 15 min and a Km of 99.8 +/- 29.9 microM. The estimated coupling ratio of Na+ and taurine was 1.80 +/- 0.122. Na(+)-dependent taurine uptake was significantly inhibited by beta-amino acids, but not by alpha-amino acids, indicating that the transporter is selective for beta-amino acids. Na(+)-dependent taurine uptake showed some selectivity for anions: the accumulation was comparable in the presence of Cl-, Br- and thiocyanate whereas I-, SO4(2-) and gluconate did not stimulate the uptake significantly. Collectively, our results demonstrate that taurine is transported in the choroid plexus via a Na(+)-dependent, saturable and apparently beta-amino acid selective mechanism. This process may be functionally relevant to taurine homeostasis in the brain.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0006-3002
pubmed:author
pubmed:issnType
Print
pubmed:day
13
pubmed:volume
1193
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
10-6
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Characterization of a sodium-dependent taurine transporter in rabbit choroid plexus.
pubmed:affiliation
Department of Pharmacy, University of California, San Francisco 94143.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.