Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1992-2-13
pubmed:abstractText
The effects on the cytosolic Ca2+ concentration of activating cholecystokinin receptors on single mouse pancreatic acinar cells have been investigated using patch-clamp whole-cell recording of Ca(2+)-dependent Cl- current. We used the nonsulphated octapeptide of cholecystokinin (CCK8-NS) since the effects of even high concentrations were rapidly reversible which was not the case for the sulphated octapeptide. A submaximal concentration of CCK8-NS (10 nM) evoked a current response consisting of short-lasting (a few seconds) spikes, and some of these spikes were seen to trigger larger and longer (about half a minute) current pulses. At a higher concentration (100 nM) CCK8-NS evoked smooth and sustained responses. The effect of CCK8-NS was almost abolished when the internal perfusion solution contained a high concentration of the Ca2+ chelator EGTA (5 mM). The responses evoked by CCK8-NS were independent of the presence of Ca2+ in the external solution at least for the first 5 min of stimulation. Internal perfusion with GTP-gamma-S markedly potentiated the effect of CCK8-NS or at a higher concentration itself induced responses very similar to those normally evoked by CCK8-NS. Caffeine added to the external solution at a low concentration (0.2-1 mM) enhanced weak CCK8-NS responses, whereas high caffeine concentrations always inhibited the CCK8-NS-evoked responses. These inhibitory caffeine effects were quickly reversible. Forskolin evoked a similar inhibitory effect. Intracellular heparin (200 micrograms/ml) infusion markedly inhibited the response to CCK8-NS stimulation. We conclude that the primary effect of activating CCK receptors is to induce inositoltrisphosphate (IP3) production.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-2631
pubmed:author
pubmed:issnType
Print
pubmed:volume
124
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
179-87
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Cytoplasmic Ca2+ signals evoked by activation of cholecystokinin receptors: Ca(2+)-dependent current recording in internally perfused pancreatic acinar cells.
pubmed:affiliation
Physiological Laboratory, University of Liverpool, United Kingdom.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't