Linked Life Data

9570802

Source:http://linkedlifedata.com/resource/pubmed/id/9570802

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
10
pubmed:dateCreated
1998-6-1
pubmed:abstractText
Combined electrophysiological and imaging techniques were used to study calcium currents (ICa) and their sites of origin at rod bipolar cells in rat retinal slices. We report here for the first time the successful whole-cell patch-clamp recording from presynaptic boutons that were compared with somatic recordings. TTX-resistant inward currents were elicited in response to depolarization. The kinetic and pharmacological properties of ICa were very similar for recordings obtained from the soma and the presynaptic terminals. ICa activated maximally between -30 and -20 mV was enhanced by Bay K 8644 and was blocked by isradipine and nifedipine. Peak amplitude and time to peak were -31.3 +/- 1.2 pA and 3.2 +/- 0.2 msec with somatic recordings (n = 54), whereas the corresponding values were -31.6 +/- 6.1 pA and 3.2 +/- 0.7 msec in recordings obtained directly from terminals (n = 6). ICa showed little inactivation during sustained depolarizations. No T-type ICa was observed with depolarizations from -90 mV. Concomitant with Ca2+ entry, depolarization induced the appearance of transient outward currents that resembled IPSCs and were blocked by GABA and glycine receptor antagonists, suggesting that they arise from activation of amacrine feedback synapses. Upon depolarization, intracellular Ca2+ ([Ca2+]i) rises were restricted to the presynaptic terminals with no somatic or axonal changes and were linearly dependent on pulse duration when using a low-affinity Ca2+ indicator. In cone bipolar cells, ICa inactivated markedly, and [Ca2+]i rises occurred in the axon, as well as in the presynaptic terminals.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0270-6474
pubmed:author
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
18
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
3715-24
pubmed:dateRevised
2008-11-21
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Calcium currents and calcium signaling in rod bipolar cells of rat retinal slices.
pubmed:affiliation
Arbeitsgruppe Zelluläre Neurobiologie, Max-Planck-Institut für biophysikalische Chemie, 37070 Göttingen, Germany.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't