Linked Life Data

1872368

Source:http://linkedlifedata.com/resource/pubmed/id/1872368

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2 Pt 1
pubmed:dateCreated
1991-9-19
pubmed:abstractText
Extracellular Li+ has been known to facilitate the basal secretion of growth hormone from anterior pituitary cells and of catecholamine from chromaffin cells. In both cases, the intracellular accumulation of Li+ seems to be the prerequisite, and the presence of extracellular Ca2+ is indispensable. In this series of experiments, we examined whether Li+ blocked K+ currents by using primary cultured anterior pituitary cells from male rats. K+ currents were measured in the whole cell configuration of the patch-clamp technique. Extracellular Li+ (140 mM) suppressed both the delayed rectifier K+ current (IK) and the transient outward K+ current to 71 and 69% of control, respectively, in a reversible manner. IK elicited by a voltage step to +70 mV from holding potential of -70 mV was suppressed by 32.5 mM internal Li+ to 28% of control. Half-maximal suppression of K+ conductance by internal Li+ was 16 mM. Furthermore, Ca(2+)-channel blocker methoxyverapamil potently suppressed Li(+)-induced growth hormone secretion. From these results we propose that the blockade by Li+ of K+ channels could depolarize the cells and activate Ca2+ channels, thereby promoting the influx of Ca2+ and hormone secretion as a mechanism of Li(+)-induced hormone secretion.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0002-9513
pubmed:author
pubmed:issnType
Print
pubmed:volume
261
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
C218-23
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Blockade by lithium ions of potassium channels in rat anterior pituitary cells.
pubmed:affiliation
Laboratoire de Neurobiologie des Comportements, Institut National de la Santé, et de la Recherche Médicale Unité 176, Bordeaux, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't