[Stimulation of delta1-opioid receptors increases the ventricular fibrillation threshold in post-infarct cardiosclerosis: the role of K(ATP)-channels].
Preliminary administration of the delta 1-opioid receptor (delta 1-OR) selective peptide agonist DPDPE (0.1 mg/kg, i.v.) increased the ventricular fibrillation threshold (VFT) in postinfarction cardiosclerosis in rats. Pretreatment with the selective delta 1-OR antagonists ICI 174,864 (not affecting VFT) in a dose of 0.5 mg/kg completely eliminated the DPDPE-induced increase in the VFT. Pretreatment with the KATP channel selective blocker glibenclamide (0.3 mg/kg, i.v.) completely eliminated the delta 1-OR mediated increase in the VFT protective effect of the delta 1-OR stimulation. The intravenous injection of the mitochondrial KATP channel blocker 5-hydroxydecanoate (5 mg/kg) simultaneously with DPDPE not only eliminated the delta 1-OR mediated increase on VFT, but additionally increased the VBFT drop caused by cardiosclerosis. Injected separately, neither glibenclamide nor hydroxydecanoate affected the VFT level. It is concluded that stimulation of the delta 1-OR increases VFT by activating mitochondrial KATP-channels.
Solenkova
N V
NV
Department of Biochemistry, Siberian State Medical University, Moskovskii trakt 2, Tomsk, 634050 Russia.
Maslov
L N
LN
Lishmanov
Iu B
IuB
Serebrov
V Iu
VIu
Bogomaz
S A
SA
Gross
G G
GG
Stefano
J B
JB
Tam
S V
SV
D000255:Adenosine Triphosphate / Q000502:physiology*; D000818:Animals; D020881:Enkephalin, D-Penicillamine (2,5)- / Q000494:pharmacology; D004743:Enkephalin, Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D005905:Glyburide / Q000494:pharmacology; D008929:Mitochondria, Heart / Q000378:metabolism; D009203:Myocardial Infarction / Q000150:complications*; D009206:Myocardium / Q000378:metabolism / Q000473:pathology*; D026902:Potassium Channel Blockers / Q000494:pharmacology; D015221:Potassium Channels / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D017465:Receptors, Opioid, delta / Q000819:agonists*; D012598:Sclerosis; D014693:Ventricular Fibrillation / Q000209:etiology / Q000378:metabolism / Q000517:prevention & control*
D026902:Potassium Channel Blockers; D015221:Potassium Channels; D017465:Receptors, Opioid, delta; D004743:Enkephalin, Leucine; D020881:Enkephalin, D-Penicillamine (2,5)-; C040643:N,N-diallyl-tyrosyl-alpha-aminoisobutyric acid-phenylalanyl-leucine; D000255:Adenosine Triphosphate; D005905:Glyburide