Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
9
pubmed:dateCreated
1999-3-30
pubmed:abstractText
The addition of the alpha-ketoaldehyde methylglyoxal (0.5 or 1 mmol/L) to single isolated rat pancreatic beta-cells caused a rapid, marked depolarization resulting in electrical activity. This effect of methylglyoxal on beta-cell was reversible upon removal of the alpha-ketoaldehyde, and could be inhibited by the anion channel blockers 4,4'-diisothiocyanatostilbene-2,2'-disulphonic acid (DIDS) and 5-nitro-2-(3-phenylpropylamino) benzoic acid (NPPB). Methylglyoxal also resulted in elevated cytosolic [Ca2+] and an intracellular acidification in intact rat islets. In perifused islets, methylglyoxal provoked a modest, transient stimulation of secretion but inhibited glucose-induced insulin release. Incubation of islets with methylglyoxal resulted in the formation of large quantities of D-lactate, indicating metabolism of the alpha-ketoaldehyde via the glyoxalase pathway. The effects of methylglyoxal on beta-cell membrane potential, cytosolic [Ca2+] and intracellular pH were also observed in response to phenylglyoxal which is also effectively metabolized via the glyoxalase pathway. However, t-butylglyoxal which is poorly metabolized via the glyoxalase pathway, caused neither depolarization of the membrane potential nor intracellular acidification, but did inhibit glucose-induced insulin release. These findings suggests that the depolarization and acidification evoked by methyl- and phenylglyoxal are dependent upon their metabolism via the glyoxalase pathway. The possible mechanisms coupling alpha-ketoaldehyde metabolism via the glyoxalase pathway with membrane depolarization are discussed.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-2952
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
55
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1361-7
pubmed:dateRevised
2011-11-17
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
Effects of methylglyoxal on rat pancreatic beta-cells.
pubmed:affiliation
Department of Medicine, University of Manchester, Oxford, U.K.
pubmed:publicationType
Journal Article, In Vitro, Research Support, Non-U.S. Gov't