Linked Life Data

1491278

Source:http://linkedlifedata.com/resource/pubmed/id/1491278

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
12
pubmed:dateCreated
1993-3-2
pubmed:abstractText
The permeability of the normal round window membrane of the guinea pig to trimethylphenylammonium (TMPA) was assessed using ion-selective electrodes and compared with the rate of TMPA entry from the systemic blood circulation into the scala tympani (ST) of the cochlea across the so-called blood-labyrinth barrier. While the round window niche was irrigated with artificial perilymph containing 1 mM TMPA, the TMPA concentration in ST of the basal turn rose rapidly so as to reach 20-50% of the irrigating medium concentration in one hour. Following this procedure, the concentration declined significantly faster when the niche was subsequently irrigated with TMPA-free artificial perilymph than when the niche was left free of any fluid. This result shows that the membrane is fairly permeable to TMPA in both directions. Furthermore, TMPA entry from blood to STs of the basal and third turns was observed while the plasma TMPA concentration was maintained at about 0.5 mM by continuous intravenous infusion of isotonic 50 mM TMPA medium (1 part 150 mM TMPA + 2 parts lactated Ringer solution). TMPA appeared to distribute evenly from the blood to both turns at a much slower rate than across the round window membrane. In another experiment, the round window niche was irrigated with TMPA-free artificial perilymph during the intravenous infusion of 50 mM TMPA medium. The TMPA concentration increase in ST of the basal turn was greatly suppressed, whereas that of the third turn was not affected for at least an hour.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
jpn
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0030-6622
pubmed:author
pubmed:issnType
Print
pubmed:volume
95
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1959-67
pubmed:dateRevised
2011-7-28
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
[Solute movement across the round window membrane in comparison with that across the blood-labyrinth barrier].
pubmed:affiliation
Institute of Clinical Medicine, University of Tsukuba.
pubmed:publicationType
Journal Article, English Abstract