Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1994-9-28
pubmed:abstractText
Rat dorsal root ganglion neurons are endowed with tetrodotoxin-sensitive(TTX-S) and tetrodotoxin-resistant (TTX-R) sodium channels. The pyrethroid insecticides, which are known to keep sodium channels open for a prolonged period of time, cause differential effects on the two types of sodium channels. The whole-cell patch clamp experiments were performed with rat dorsal root ganglion neurons in primary culture. In TTX-S sodium channels, the slow sodium current during step depolarization was increased somewhat by tetramethrin, and a tail sodium current with a slowly rising and falling phase appeared upon repolarization. The tail current developed even after the sodium current during depolarization had subsided. In TTX-R sodium channels, the slow sodium current during step depolarization was increased markedly by tetramethrin, and upon repolarization a large instantaneous tail current was generated and decayed slowly. The steady-state sodium channel inactivation curve was shifted by tetramethrin in the hyperpolarizing direction in both TTX-S and TTX-R channels. The sodium conductance-voltage curve also was shifted by tetramethrin in the hyperpolarizing direction in both TTX-S and TTX-R channels, and the latter was affected more strongly than the former. At a concentration of 10 microM, the highest concentration tested, tetramethrin modified only 12% of the TTX-S sodium channels, whereas the modification was as high as 81% in the TTX-R. Even at 10 nM, 1.3% of TTX-R sodium channels were modified; this accounts for the high potency of tetramethrin as an insecticide.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
270
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
595-603
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Differential mechanism of action of the pyrethroid tetramethrin on tetrodotoxin-sensitive and tetrodotoxin-resistant sodium channels.
pubmed:affiliation
Department of Pharmacology, Northwestern University Medical School, Chicago, Illinois.
pubmed:publicationType
Journal Article, In Vitro, Research Support, U.S. Gov't, P.H.S.