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| Predicate | Object |
|---|---|
| rdf:type | |
| lifeskim:mentions | |
| pubmed:issue |
30
|
| pubmed:dateCreated |
1993-12-1
|
| pubmed:abstractText |
The action of arginine vasopressin (AVP) on cytosolic free Ca2+ concentration ([Ca2+]i) was investigated in single rat pituitary corticotrophs using indo-1 microfluorimetry, in part in combination with the monitoring of membrane electrical events with the perforated patch-clamp technique. In corticotrophs showing the series of short-lived [Ca2+]i rises (transient pattern) in response to corticotropin-releasing factor, 100 nM AVP evoked either the transient pattern or a [Ca2+]i spike followed by a sustained plateau (spike/plateau pattern). Not all corticotrophs responded to changes in AVP concentration in the same manner. Some cells exhibited a concentration-dependent increase in [Ca2+]i transient activity, whereas others showing the spike/plateau at high AVP concentrations responded to low agonist concentrations by two [Ca2+]i responses: a slow rising step or two to three sinusoidal-like oscillations. Combined [Ca2+]i and patch-clamp recordings as well as manipulation of extracellular Ca2+ showed that both transient pattern and the plateau of spike/plateau response depended on Ca2+ entry mainly through voltage-gated, dihydropyridine-sensitive Ca2+ channels. By contrast, step, oscillations, and spike were due to Ca2+ release from internal stores. These Ca(2+)-mobilizing responses caused the activation of Ca(2+)-activated, apamin-sensitive K+ channels, which led to a membrane hyperpolarization. These results reveal cell-specific [Ca2+]i signals and associated electrical events in individual AVP-stimulated corticotrophs.
|
| pubmed:language |
eng
|
| pubmed:journal | |
| pubmed:citationSubset |
IM
|
| pubmed:chemical |
http://linkedlifedata.com/resource/pubmed/chemical/Arginine Vasopressin,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium,
http://linkedlifedata.com/resource/pubmed/chemical/Calcium Channel Blockers,
http://linkedlifedata.com/resource/pubmed/chemical/Ionomycin,
http://linkedlifedata.com/resource/pubmed/chemical/Isradipine,
http://linkedlifedata.com/resource/pubmed/chemical/Sodium Channel Blockers,
http://linkedlifedata.com/resource/pubmed/chemical/Tetrodotoxin
|
| pubmed:status |
MEDLINE
|
| pubmed:month |
Oct
|
| pubmed:issn |
0021-9258
|
| pubmed:author | |
| pubmed:issnType |
Print
|
| pubmed:day |
25
|
| pubmed:volume |
268
|
| pubmed:owner |
NLM
|
| pubmed:authorsComplete |
Y
|
| pubmed:pagination |
22313-21
|
| pubmed:dateRevised |
2006-11-15
|
| pubmed:meshHeading |
pubmed-meshheading:8226740-Animals,
pubmed-meshheading:8226740-Arginine Vasopressin,
pubmed-meshheading:8226740-Calcium,
pubmed-meshheading:8226740-Calcium Channel Blockers,
pubmed-meshheading:8226740-Cell Membrane,
pubmed-meshheading:8226740-Cells, Cultured,
pubmed-meshheading:8226740-Cytosol,
pubmed-meshheading:8226740-Dose-Response Relationship, Drug,
pubmed-meshheading:8226740-Ionomycin,
pubmed-meshheading:8226740-Isradipine,
pubmed-meshheading:8226740-Kinetics,
pubmed-meshheading:8226740-Male,
pubmed-meshheading:8226740-Membrane Potentials,
pubmed-meshheading:8226740-Pituitary Gland,
pubmed-meshheading:8226740-Rats,
pubmed-meshheading:8226740-Rats, Sprague-Dawley,
pubmed-meshheading:8226740-Sodium Channel Blockers,
pubmed-meshheading:8226740-Tetrodotoxin,
pubmed-meshheading:8226740-Time Factors
|
| pubmed:year |
1993
|
| pubmed:articleTitle |
Multiple cytosolic calcium signals and membrane electrical events evoked in single arginine vasopressin-stimulated corticotrophs.
|
| pubmed:affiliation |
Laboratoire de Neurophysiologie, Université de Bordeaux, France.
|
| pubmed:publicationType |
Journal Article,
Research Support, Non-U.S. Gov't
|