| 1. |
- Bobrova, Irina, et al.
(författare)
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A structure-activity study of nociceptin-(1-13)-peptide amide. Synthesis of analogues substituted in positions 0, 1, 3, 4 and 10.
- 2003
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Ingår i: European journal of medicinal chemistry. - 0223-5234. ; 38:7-8, s. 687-694
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Tidskriftsartikel (refereegranskat)abstract
- A series of analogues of nociceptin, Noc(1-13)NH(2) (an agonist at the ORL1 receptor) was synthesized with following modifications: (1) N-terminal extension with Arg(0); (2) replacement of Gly(3) by basic or polar amino acids-Arg, Asn, Lys(For) or deletion; (3) exchange of Phe(1) or Phe(4) by Phe(NO(2)); (4) substitution of Ser(10) with D-Ser, Pro, D-Pro. The analogs were synthesized by solid-phase methodology using Fmoc-amino acid pentafluorophenyl esters. The affinity for the ORL1 and for the kappa, micro and delta-opioid receptors was investigated by radioligand binding assay and bioactivity by a mouse vas deferens (MVD) assay. The addition of the amino acid residue Arg to the N-terminal enhances the opioid receptor affinity of Noc(1-13)NH(2) while retaining ORL1 receptor affinity at a moderate level. The replacement of Gly in position 3 by the basic or polar amino acids-Arg, Asn, Lys(For) or its deletion led to inactive analogues. The replacement of Ser in position 10 by its D-isomer, Pro and D-Pro resulted in a series of analogues with the following order of activity: Ser(10)>D-Ser(10)>Pro(10)>D-Pro(10). In [D-Ser(10)]Noc(1-13)NH(2), introduction of an additional Phe(NO(2))(4) led to a >60-fold increase of ORL1 affinity, completely attenuating the loss of affinity brought about by Ser(10). In other analogues, introduction of Phe(NO(2))(4) did not change the magnitude of ORL1 binding significantly. Generally, while modifications in position 3 frequently led to a loss of most or all bioactivity, modifications in position 0 (Arg(0)) or 4 (Phe(NO(2))(4)) and 10 (D-Ser(10), Pro(10)) are tolerated.
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| 2. |
- Karlsson, Lars O, 1975, et al.
(författare)
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Opioid receptor agonist Eribis peptide 94 reduces infarct size in different porcine models for myocardial ischaemia and reperfusion
- 2011
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Ingår i: European Journal of Pharmacology. - : Elsevier BV. - 0014-2999 .- 1879-0712. ; 651:1-3, s. 146-151
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Tidskriftsartikel (refereegranskat)abstract
- Eribis peptide 94 (EP 94) is a novel enkephalin analog, thought to interact with the and delta-opioid receptors. The purpose of the present study was to examine the cardioprotective potential of EP 94 in two clinically relevant porcine models of myocardial ischaemia and reperfusion, and to investigate if such an effect is associated with an increased expression of endothelial nitric oxide synthase (eNOS). Forty-one anesthetized pigs underwent 40 min of coronary occlusion followed by 4 h of reperfusion. In Protocol I, balloon occlusion of the left anterior descending artery was performed with concurrent intravenous administration of (A) vehicle (n = 7), (B) EP 94 (1 ug/kg) after 5, 12, 19 and 26 min of ischaemia (n = 4) or (C) EP 94 (1 ug/kg) after 26, 33, 40 min of ischaemia (n = 6). In Protocol II, open-chest pigs were administered (D) vehicle (n = 6) or (E) 0.2 ug/kg/min of EP 94 (n = 6) through an intracoronary infusion into the jeopardized myocardium, started after 30 min of ischaemia and maintained for 15 min. The hearts were stained and the protein content of eNOS measured. EP 94 reduces infarct size when administered both early and late during ischaemia compared with vehicle (infarct size group A 61.6 +/- 2%, group B 50.2 +/- 3% and group C 49.2 +/- 2%, respectively, P < 0.05), as well as when infused intracoronary (infarct size group D 82.2 +/- 3.9% and group E 61.2 +/- 2.5% respectively, P < 0.01). Phosphorylated eNOS Ser(I177) in relation to total eNOS was significantly increased in the group administered EP 94. indicating activation of nitric oxide production.
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| 3. |
- Spanos, Elias, et al.
(författare)
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Cardioprotection of the enkephalin analog Eribis peptide 94 in a rat model of ischemia and reperfusion is highly dependent on dosing regimen and timing of administration
- 2015
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Ingår i: European Journal of Pharmacology. - : Elsevier BV. - 0014-2999. ; 747, s. 1-6
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Tidskriftsartikel (refereegranskat)abstract
- Eribis Peptide 94 (EP94) is an enkephalin analog with cardioprotective properties in ischemia and reperfusion. The aim of the present study was to define the optimal timing and dosing of the administration of EP94 during ischemia and reperfusion in a rat model. 172 anesthetized and mechanically ventilated male Sprague-Dawley rats were randomly assigned to different administration protocols of EP94 and subjected to 30 or 40min of coronary artery occlusion followed by 2h of reperfusion. EP94 was administered intravenously at different doses and time intervals. Area at risk (AAR) and infarct size (IS) were determined by staining with Evans Blue (EB) and Triphenyl tetrazolium chloride (TTC), respectively. EP94 reduced IS/AAR when administered as a double bolus (0.5µg/kg per dose), whereas single (1μg/kg) or triple boluses (0.5μg/kg per dose) did not confer any protection. Reduction of IS/AAR was of highest magnitude if EP94 was administered 5 and 0min before the 30min ischemic period (47% reduction, P<0.05), with declining cardioprotective effect with later administration during ischemia. When EP94 was administered after 15 and 20min of a 40-min ischemic period, reduction of IS/AAR was of the same magnitude as when given after 5 and 10min of a 30-min ischemic period. It is concluded that EP94 confers cardioprotection after double bolus administration. The effects are highly dependent on the timing of administration in relation to ischemia and reperfusion. Time of reperfusion from drug administration seems to be more critical than the total duration of ischemia.
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