| Secretagogue-evoked changes in intracellular free magnesium concentrations in rat pancreatic acinar cells. | |
| | |
MedLine Citation:
|
PMID: 1770445 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
1. This study employs the fluorescent dye Mag-Fura-2 acetoxymethyl ester (AM) to measure intracellular free magnesium concentration [Mg2+]i in isolated rat pancreatic acinar cells. Initially a number of protocols were investigated to develop optimal loading conditions for the dye Mag-Fura-2 AM. The procedure yielding cells which showed minimal dye loss and no adverse compartmentalization was adopted for subsequent experiments. 2. The mean resting [Mg2+]i is 1.39 +/- 0.08 mM (n = 39). 3. Acetylcholine (ACh), cholescystokinin-octapeptide (CCK8), carbamylcholine chloride evoked marked reduction in [Mg2+]i in pancreatic acinar cells compared to resting values in the absence of secretagogues. The ACh-evoked decrease in [Mg2+]i was abolished by pre-treatment with atropine. In contrast, noradrenaline, adrenaline and histamine had no significant effect on [Mg2+]i. 4. In acinar cells loaded with the Ca(2+)-sensitive dye, Fura-2 acetoxymethyl ester (AM), ACh stimulation resulted in a marked elevation in intracellular free Ca2+ concentration [Ca2+]i. This response was blocked by pre-treatment with atropine. 5. Atomic absorption spectrophotometry was used to measure Mg2+ levels in effluent samples from pancreatic segments. Stimulation of pancreatic segments with ACh resulted in a marked elevation in Mg2+ concentrations (net efflux). On removal of ACh, Mg2+ concentration returned to resting level followed by a small net influx of Mg2+ into pancreatic tissue. 6. The results demonstrate that secretagogue-evoked alteration in [Mg2+]i may occur concurrently with Mg2+ release from pancreatic tissue. |
| | |
Authors:
|
R Lennard; J Singh |
Related Documents
:
|
6894545 - Interaction of calcium with bovine plasma protein c. 21974595 - Independently driven four-probe method for local electrical characteristics in organic ... 2150215 - Identification of a spectroscopic marker for the ca2(+)-binding site of (ca2+ + mg2+)-a... 9372145 - Regulation of calcium currents and secretion by magnesium in crustacean peptidergic neu... 21157525 - Variability in measures of exhaled breath na, influence of pulmonary blood flow and sal... 9449325 - Properties of herg channels stably expressed in hek 293 cells studied at physiological ... |
Publication Detail:
|
Type: Journal Article; Research Support, Non-U.S. Gov't |
Journal Detail:
|
Title: The Journal of physiology Volume: 435 ISSN: 0022-3751 ISO Abbreviation: J. Physiol. (Lond.) Publication Date: 1991 Apr |
Date Detail:
|
Created Date: 1992-02-24 Completed Date: 1992-02-24 Revised Date: 2010-08-25 |
Medline Journal Info:
|
Nlm Unique ID: 0266262 Medline TA: J Physiol Country: ENGLAND |
Other Details:
|
Languages: eng Pagination: 483-92 Citation Subset: IM |
Affiliation:
|
School of Applied Biology, Lancashire Polytechnic. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Acetylcholine
/
physiology Animals Carbachol / pharmacology Fura-2 / analogs & derivatives, diagnostic use Magnesium / analysis, metabolism* Pancreas / chemistry, metabolism* Rats Rats, Inbred Strains Sincalide / physiology Spectrometry, Fluorescence Spectrophotometry, Atomic |
| Grant Support | |
ID/Acronym/Agency:
|
//Wellcome Trust |
| Chemical | |
Reg. No./Substance:
|
130100-20-8/Mag-Fura-2-acetoxymethyl ester; 25126-32-3/Sincalide; 51-83-2/Carbachol; 51-84-3/Acetylcholine; 7439-95-4/Magnesium; 96314-98-6/Fura-2 |
| Comments/Corrections | |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Depression of a sustained calcium current by kainate in rat hippocampal neurones in vitro.
Next Document: The voltage responses of hair cells in the basal turn of the guinea-pig cochlea.