Linked Life Data

10087149

Source:http://linkedlifedata.com/resource/pubmed/id/10087149

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1999-6-4
pubmed:abstractText
The recently cloned rabbit kidney Ca2+-sensing receptor (RabCaR) was functionally characterized in microperfused rabbit cortical thick ascending limb (CTAL) segments. Reverse transcriptase polymerase chain reaction (RT-PCR) confirmed that this nephron segment contains mRNAs coding for the RabCaR. Elevation of the extracellular Ca2+ concentration ([Ca2+]e) from 1 to 5 mmol l-1 induced an increase in the fluorescence emission ratio (R), thus reflecting an increase in intracellular Ca2+ activity ([Ca2+]i). This increase was inhibited by verapamil, nifedipine and SKF 96365, and potentiated by a previous application of Bay K 8644. Neither verapamil nor Bay K 8644 modified the resting [Ca2+]i. This suggests that the basolateral Ca2+ influx induced by a high [Ca2+]e occurs via verapamil- and dihydropyridine-sensitive Ca2+ channels, which are not open under resting conditions. In contrast to that evoked by antidiuretic hormone (ADH), the [Ca2+]i increase induced by a high [Ca2+]e did not result from an accumulation of inositol phosphates. Neomycin, Gd3+, Mg2+, commonly used agonists of the Ca2+-sensing receptor, did not increase the [Ca2+]i. In the presence of verapamil, ADH still produced a transient [Ca2+]i increase that was not observed in the presence of an increased [Ca2+]e. These results suggest that the RabCaR in rabbit CTAL cells is not functionally coupled to phospholipase C. In conclusion, the high [Ca2+]e-induced [Ca2+]i increase involves verapamil- and dihydropyridine-sensitive Ca2+ channels and is independent of phosphoinositide metabolism. Whether these channels are activated by the RabCaR remains to be elucidated.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0031-6768
pubmed:author
pubmed:issnType
Print
pubmed:volume
437
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
716-23
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed-meshheading:10087149-Animals, pubmed-meshheading:10087149-Calcium, pubmed-meshheading:10087149-Calcium Channels, pubmed-meshheading:10087149-Calcium Signaling, pubmed-meshheading:10087149-Female, pubmed-meshheading:10087149-Inositol Phosphates, pubmed-meshheading:10087149-Ion Channel Gating, pubmed-meshheading:10087149-Kidney Cortex, pubmed-meshheading:10087149-Nephrons, pubmed-meshheading:10087149-Patch-Clamp Techniques, pubmed-meshheading:10087149-Phosphoric Diester Hydrolases, pubmed-meshheading:10087149-RNA, Messenger, pubmed-meshheading:10087149-Rabbits, pubmed-meshheading:10087149-Receptors, Calcium-Sensing, pubmed-meshheading:10087149-Receptors, Cell Surface, pubmed-meshheading:10087149-Renal Agents, pubmed-meshheading:10087149-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:10087149-Spectrometry, Fluorescence, pubmed-meshheading:10087149-Type C Phospholipases, pubmed-meshheading:10087149-Vasopressins
pubmed:year
1999
pubmed:articleTitle
The Ca2+-sensing receptor in the rabbit cortical thick ascending limb (CTAL) is functionally not coupled to phospholipase C.
pubmed:affiliation
Département de Biologie Cellulaire et Moléculaire, CEA Saclay, URA CNRS 1859, F-91191 Gif-sur-Yvette, France.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't