Linked Life Data

1851633

Source:http://linkedlifedata.com/resource/pubmed/id/1851633

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:dateCreated
1991-6-27
pubmed:abstractText
Propionyl-L-carnitine (PC) protects perfused rat hearts against damage by ischemia-reperfusion. Activation of L-type calcium channel play a role on ischemia-reperfusion damage. Therefore, we studied the effect of PC on some properties of L-type calcium channels in an in vitro preparation from human myocardium sarcolemma (from patients with idiopathic dilated cardiomyopathy). Binding of the L-type calcium channel blockers isradipine [3H]-PN 200-110 (PN) to plasma membrane preparations revealed a single population of binding sites (total number: Bmax = 213 +/- 34 fM/mg protein and affinity: Kd = 152 +/- 19 nM; n = 6). The characteristics of these binding sites were evaluated in the presence and in the absence of Ca2+ and of calcium blockers (D-888, a verapamillike drug, and diltiazem). Incubation in a Ca2(+)-containing buffer increased the affinity of PN binding sites. Binding sites for PN were modulated by organic calcium channel blockers; in competition isotherms at 37 degrees C, D-888 (desmethoxyverapamil) decreased the PN binding, whereas diltiazem increased it. These results strongly suggest that the site labelled by PN is the voltage-operated calcium channel of the human myocardium. The addition of PC (1 mM) to plasma membranes labelled with PN at 37 degrees C decreased the affinity of the binding; this effect was counteracted by the addition of Ca2+ to the medium. This result was consistent with a competition between Ca2+ and PC. The effect of PC incubation at 4 degrees C was the opposite; at this temperature PC increased the affinity of the binding sites and the effect was obscured by Ca2+.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0920-3206
pubmed:author
pubmed:issnType
Print
pubmed:volume
5 Suppl 1
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
31-5
pubmed:dateRevised
2004-11-17
pubmed:meshHeading
pubmed:year
1991
pubmed:articleTitle
Effect of propionyl-L-carnitine on L-type calcium channels in human heart sarcolemma.
pubmed:affiliation
Servizio di Endocrinologia, Ospedale L. Sacco (Vialba), Milano, Italy.
pubmed:publicationType
Journal Article