Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1996-12-4
pubmed:abstractText
To determine whether the charybdotoxin-sensitive subtypes of voltage-gated K+ channels (Kv1.2 and Kv1.3) exist in inhibitory pre-synaptic terminals, effects of K+ channel blockers including TEA, charybdotoxin (ChTX), iberiotoxin (IbTX), kaliotoxin (KTX) and margatoxin (MgTX) on the inhibitory transmission were examined with cultured rat hippocampal neurons. Monosynaptic inhibitory postsynaptic currents (IPSCs) evoked by electrical stimulation of single presynaptic neurons were recorded from the whole-cell clamped postsynaptic neurons. In the presence of TEA, application of ChTX greatly increased the amplitude of IPSCs. A specific maxi-K+ channel blocker IbTX failed to augment IPSCs. KTX and MgTX, both of which block Kv1.3 but not Kv1.2, mimicked the facilitating effect of ChTX. In the absence of TEA, application of ChTX increased the IPSC amplitude significantly, while IbTX was without effect. These results indicate that the ChTX-sensitive subtypes of voltage-gated K+ channels, most likely Kv1.3, contribute to the repolarization of action potentials at presynaptic terminals of hippocampal inhibitory neurons, and that the ChTX-induced facilitation of the transmission can be explained by its effects on the Kv channels rather than maxi-K+ channels.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0304-3940
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
207
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
195-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1996
pubmed:articleTitle
Presence of the voltage-gated potassium channels sensitive to charybdotoxin in inhibitory presynaptic terminals of cultured rat hippocampal neurons.
pubmed:affiliation
Department of Physiology, Faculty of Medicine, Kanazawa University, Japan.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't