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Cucumel K, Garreau I, Mery J, Moinier D, Mansour A, Akil H, Cupo A. Production and characterization of site-directed antibodies against dermorphin and dermorphin-related peptides. Peptides 1996; 17:973-82. [PMID: 8899816 DOI: 10.1016/0196-9781(96)00113-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
To detect and purify endogenous dermorphin-like molecules in mammalian tissues, an immunological approach was developed. Site-directed antibodies against synthetic dermorphin and related dermorphin peptides were produced. The immunogenic forms of dermorphin were selected to obtain antibodies recognizing different epitopes overlapping the whole dermorphin molecule. One of them specifically recognized the crucial "opioid message" (the N-terminal part of the molecule), which is required for a ligand to exert its full opioid activity. The validity of our immunological approach was analyzed by studying the dermorphin-related peptide distribution in Phyllomedusa sauvagei skin. The finding that tetrapeptide Y-A-G-F-OH was present in Phyllomedusa sauvagei extracts suggested that either the Tyr3-Pro6 peptidic bond may be relatively unstable or endogenous proteolytic enzymes present in Phyllomedusa skin may inactivate this peptidic bond.
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Affiliation(s)
- K Cucumel
- Institut de Pharmacologie Moléculaire et Cellulaire CNRS-UPR411, Valbonne, France
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202
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Gioanni Y, Greco B, Prevost J. Search for the structures initiating seizures triggered by intraventricular injection of the mu opioid agonist dermorphin in rats. Epilepsia 1995; 36:922-8. [PMID: 7649132 DOI: 10.1111/j.1528-1157.1995.tb01636.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Free-moving rats received intraventricular (i.c.v.) or intravenous (i.v.) injections of the mu opioid agonist dermorphin (DRM). The EEG activity of the cortex and of several structures near the injected lateral ventricle was recorded. The intravenous injections of DRM did not induce epileptiform activity. The intracerebroventricular injections of DRM triggered several types of electrical seizures and interictal spikes. With the aim of determining which structure gave rise to the epileptiform discharges, we compared the time relationships of epileptiform phenomena occurring in different structures. Epileptiform discharges, at once generalized, appeared first in the CA3 area of the ventral hippocampus, with involvement of the CA1 area of ventral hippocampus, the entorhinal cortex and the amygdala following immediately. We conclude that, after intracerebroventricular injection of a mu opiate agonist, epileptiform activity originates in the CA3 area of the ventral hippocampus.
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Affiliation(s)
- Y Gioanni
- INSERM, Centre Paul Broca, Paris, France
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203
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Lavidis NA. The effect of opiates on the terminal nerve impulse and quantal secretion from visualized amphibian nerve terminals. Br J Pharmacol 1995; 115:441-50. [PMID: 7582455 PMCID: PMC1908413 DOI: 10.1111/j.1476-5381.1995.tb16353.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
1. Secretion of transmitter from amphibian motor nerve terminal release sites is intermittent, spatially non-uniform and varies considerably throughout the year and during development. The role of opioid receptors in modulating transmitter secretion from amphibian motor nerve terminals is evaluated in this study. 2. Dynorphin-A (24 microM) and morphine (500 microM) did not significantly change the shape of the nerve impulse or the consistency with which it was observed, but decreased evoked quantal secretion by more than 50%. These effects of dynorphin-A and morphine were largely reversed by naloxone (50 microM). 3. Dynorphin-A and morphine did not significantly change either the amplitude or the frequency of spontaneous quantal secretions. 4. There was a uniform decrease in evoked quantal secretion from release sites along terminal branches, irrespective of the quantal content value before drug treatment, indicating no difference in the susceptibility of proximal vs distal release sites to opiates. 5. Increasing the extracellular calcium concentration (0.3 to 0.4 mM) or trains of conditioning-test impulses (25 to 100 Hz) resulted in smaller dynorphin-A or morphine-induced decreases in evoked quantal secretion. 6. The decrease in evoked quantal secretion occurs as a result of a uniform decrease in the probability of quantal secretion from release sites without any affect on the propagation of the nerve terminal impulse. Low probability release sites become effectively silent.
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Affiliation(s)
- N A Lavidis
- Department of Physiology, University of Sydney, N.S.W., Australia
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204
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Affiliation(s)
- A Borsodi
- Institute of Biochemistry, Biological Research Center, Hungarian Academy of Sciences, Szeged
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205
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Ro S, Zhu Q, Lee CW, Goodman M, Darlak K, Spatola AF, Chung NN, Schiller PW, Malmberg AB, Yaksh TL. Highly potent side chain-main chain cyclized dermorphin-deltorphin analogues: an integrated approach including synthesis, bioassays, NMR spectroscopy and molecular modelling. J Pept Sci 1995; 1:157-74. [PMID: 9222993 DOI: 10.1002/psc.310010303] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Our continuing efforts to study structure-activity relationships of peptide opioids have resulted in the synthesis of a series of cyclic opioids related to dermorphins and deltorphins. The biological activities of the compounds have been determined and the conformational analyses carried out using 1H-NMR spectroscopy and molecular modelling. The three compounds in the series Tyr-c[D-Orn-Phe-Ala], Tyr-c[D-Lys-Phe-Ala], and Tyr-c[A2bu-Phe-Ala-Leu] are cyclized via a lactam bridge from the side-chain of the residue at the second position with the carboxyl terminus of each compound. The molecules incorporate 12-, 13- and 14-membered rings, respectively. They include a phenylalanine at the third position which is a distinguishing characteristic of dermorphins and deltorphins. The guinea pig ileum and mouse vas deferens assays show that the compounds are highly active at both mu- and delta-opioid receptors. The compounds are all highly effective antinociceptive agents as measured by the intrathecal rat hot plate test. Conformational analyses of the molecules indicate that they can adopt topochemical arrays required for bioactivity at both mu- and delta-receptors which explains their high activity in both guinea pig ileum and mouse vas deferens in vitro assays. The results support our models for mu- and delta-receptor activity for constrained peptide opioids.
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Affiliation(s)
- S Ro
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla 92093-0343, USA
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207
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Lavidis NA. The effect of opiates on the secretion of transmitter from amphibian motor nerve terminals. Eur J Pharmacol 1995; 276:71-6. [PMID: 7781697 DOI: 10.1016/0014-2999(95)00007-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The effects of dynorphin-A, dermorphine and morphine on the secretion of transmitter from the toad (Bufo marinus) motor nerve terminal have been determined. Intracellular recordings of miniature end plate potentials (m.e.p.p.s) and evoked end plate potentials (e.p.p.s) were used to estimate quantal content (m) and binomial parameters p and n. Dynorphin-A, and to a lesser extent morphine, decreased (m) while dermorphine had no significant effect on m. Dynorphin-A (ED50 = 24 microM) was 21 times more potent then morphine (ED50 = 510 microM) in decreasing m. The decrease in m produced by dynorphin-A and morphine was accompanied by a greater decrease in the variance (S2) of number of quanta secreted per stimulation over the recording period. The decrease in m produced by dynorphin-A, and to a lesser extent by morphine, is probably mediated by the opiates acting on kappa-opioid receptors.
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Affiliation(s)
- N A Lavidis
- Department of Physiology, University of Sydney, N.S.W., Australia
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208
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Negri L, Lattanzi R, Melchiorri P. Production of antinociception by peripheral administration of [Lys7]dermorphin, a naturally occurring peptide with high affinity for mu-opioid receptors. Br J Pharmacol 1995; 114:57-66. [PMID: 7712029 PMCID: PMC1510172 DOI: 10.1111/j.1476-5381.1995.tb14905.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
Abstract
1. The opioid activity of the amphibian peptide, [Lys7]dermorphin, was studied in rats and mice. When administered intracerebroventricularly (i.c.v.), intravenously (i.v.) or subcutaneously (s.c.) it produced a long lasting analgesia. Its antinociceptive potency exceeded that of morphine 290 times by i.c.v. injection, and 25-30 times by peripheral administration. 2. The dose-response curves of [Lys7]dermorphin antinociception were shifted to the right by the pretreatment with naloxone (0.1 mg kg-1, s.c.) or with the mu 1-selective antagonist, naloxonazine (10 mg kg-1, i.v. 24 h before peptide injection). 3. The peptide also displayed potent antinociceptive effects in a chronic inflammatory pain model (rat Freund's adjuvant arthritis). In this pain model, systemic administration of the peptide raised the nociceptive threshold more in inflamed than in healthy paw. 4. High central and peripheral doses of [Lys7]dermorphin in rats produced catalepsy. The cataleptic response was antagonized by naloxone but left unchanged by naloxonazine pretreatment. 5. In rats and mice, central or peripheral administration of [Lys7]dermorphin induced a significantly slower development of tolerance to the antinociceptive effect than did morphine. 6. Upon naloxone precipitation of the withdrawal syndrome, [Lys7]dermorphin-dependent mice made fewer jumps and lost less weight than the morphine-dependent animals. Withdrawal hyperalgesia did not develop in [Lys7]dermorphin-dependent mice. 7. In conclusion, [Lys7]dermorphin seems to be a unique opioid peptide having a high penetration into the blood-brain barrier despite its low lipid solubility. This peptide causes fewer side-effects than other opioids and appears less likely than morphine to cause physical dependence in rats and mice.
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Affiliation(s)
- L Negri
- Institute of Medical Pharmacology, University La Sapienza, Roma, Italy
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209
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Fisher GH, Petrucelli L, Gardner C, Emory C, Frey WH, Amaducci L, Sorbi S, Sorrentino G, Borghi M, D'Aniello A. Free D-amino acids in human cerebrospinal fluid of Alzheimer disease, multiple sclerosis, and healthy control subjects. MOLECULAR AND CHEMICAL NEUROPATHOLOGY 1994; 23:115-24. [PMID: 7702702 DOI: 10.1007/bf02815405] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
This is the first report of the presence of free D-amino acids in lumbar and ventricular human cerebrospinal fluid (CSF) of individuals with Alzheimer disease (AD) compared with CSF of normal control subjects and with individuals affected by multiple sclerosis, as an unrelated neurologic disorder. Free D-amino acids are present at significantly higher levels in AD CSF than normal CSF, whereas in the CSF of patients affected by multiple sclerosis, D-amino acids occurs at the same level as in the normal controls. The total D-amino acid content in ventricular CSF was 1.48 times higher in the AD than controls (26.4 vs 17.9 nmol/mL, p = 0.025). The total D-amino acid content was 1.43 times higher in AD lumbar CSF than controls (1.89 vs 1.32 nmol/mL, p = 0.001). D-Aspartate in particular was 2.74 times higher in AD ventricular CSF compared to normal ventricular CSF (3.34 vs 1.22 nmol/mL, p = 0.029). In lumbar CSF, D-aspartate was 1.5 times higher in AD than controls (0.054 vs 0.036 nmol/mL, p = 0.041). Previously we reported that D-amino acids are elevated in AD brain proteins associated with neurofibrillary tangles compared to normal brain proteins (D'Aniello et al., 1992c; Fisher et al., 1992a,b). Thus, the D-amino acids present in CSF may originate from degradation of brain proteins.
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Affiliation(s)
- G H Fisher
- Department of Chemistry, Barry University, Miami Shores, FL 33161
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210
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Segawa M, Ohno Y, Doi M, Inoue M, Ishida T, Iwashita T. Comparative conformational analyses of mu-selective dermorphin and delta-selective deltorphin-II in aqueous solution by 1H-NMR spectroscopy. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1994; 44:295-304. [PMID: 7822107 DOI: 10.1111/j.1399-3011.1994.tb00173.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Two-dimensional 1H-NMR methods have been used to obtain complete proton resonance assignments and possible solution conformations of dermorphin (H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2) and deltorphin-II (H-Tyr-D-Ala-Phe-Glu-Val-Val-Gly-NH2), naturally occurring mu- and delta-selective opioids, respectively, in order to examine the conformational characteristics that are closely related to the selectivities towards mu/delta-opioid receptors. With the use of the proton-proton distances derived from ROESY measurements in aqueous solution, 50 possible 3D structures are generated by means of distance geometry calculations. The conformers which satisfy the distance constraints and the torsion angles estimated from JNHC alpha H vicinal coupling constants within the allowable range are then subjected to molecular dynamics simulations for 10 ps after equilibration. Although dermorphin and deltorphin-II are both in equilibrium among many flexible conformers, some conformational differences are observed between these peptides: many conformers of dermorphin show a structure rounded at the N-terminal Tyr-D-Ala-Phe-Gly-Tyr and C-terminal Gly-Tyr-Pro-Ser-NH2 moieties, which are almost at right angles to each other, while those of deltorphin-II are characterized by a 'hook'-shaped backbone structure in which the nearly extended conformation of the Val-Val-Gly-NH2 sequence is located under the folded conformation of the N-terminal Tyr-D-Ala-Phe-Glu sequence. The possible relationship between these conformational characteristics and the mu/delta-opioid receptor selectivities is discussed.
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Affiliation(s)
- M Segawa
- Department of Physical Chemistry, Osaka University of Pharmaceutical Sciences, Japan
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211
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Abstract
D-Alanine was administered orally to mutant mice lacking D-amino acid oxidase (EC 1.4.3.3). The mice had free access to drinking water containing 0.5% D- or L-alanine or 0.1% D-alanine for 2 weeks. The mice were then killed, and levels of the D- and L-enantiomers of free alanine, serine, proline, glutamate, and aspartate were determined in serum, liver, kidney, cerebrum, and cerebellum tissues. D-Alanine content increased by 60-fold (liver) to 110-fold (serum, brain), although the L-alanine level did not change. The increase of serum and brain D-alanine concentrations in animals fed 0.5% D-alanine was approximately five times more than that in animals fed 0.1% D-alanine, ie, the increase was roughly D-alanine dose-dependent in these tissues. The increase due to 0.5% D-alanine administration was reduced by 50% 17 hours after administration of D-alanine was stopped. Administration-induced increases in D-alanine levels in the cerebrum and cerebellum were not less than those in the serum, suggesting that D-alanine passed the blood-brain barrier quite freely. In the liver but not in other tissues, there were slight increases in D-serine and D-proline levels after administration of D-alanine. Administration of D-alanine produced no alterations in free glutamate and aspartate levels. No D-enantiomers of alanine, serine, proline, glutamate, or aspartate were detected in the liver and kidney tissue proteins of any animals, even in the mutant mice that received 0.5% D-alanine.
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Affiliation(s)
- Y Nagata
- Department of Life Science, Himeji Institute of Technology, Hyogo, Japan
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212
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Effect of dermorphin on the development of compensatory thermoregulatory vascular reactions under conditions of overheating. Bull Exp Biol Med 1994. [DOI: 10.1007/bf02444444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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213
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Precursors of vertebrate peptide antibiotics dermaseptin b and adenoregulin have extensive sequence identities with precursors of opioid peptides dermorphin, dermenkephalin, and deltorphins. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)32386-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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214
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Evidence for a conformational polymorphism of invertebrate neurohormones. D-amino acid residue in crustacean hyperglycemic peptides. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)32303-7] [Citation(s) in RCA: 124] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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215
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Eager KR, Robinson BJ, Galletly DC, Miller JH. Endogenous opioid modulation of hypercapnic-stimulated respiration in the rat. RESPIRATION PHYSIOLOGY 1994; 96:13-24. [PMID: 7912841 DOI: 10.1016/0034-5687(94)90102-3] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
The role of endogenous opioids in respiratory control in the pentobarbital anaesthetised rat was investigated using a rebreathing technique to generate a progressively increasing hypercapnic stimulus to the respiratory centers following administration of an opioid antagonist or agonist. Respiratory output was measured by intraesophageal pressure (IEP) changes, and a ventilatory equivalent (VEq) was calculated by multiplying IEP by respiratory rate (mmHg.min-1). A non-selective opioid antagonist, naloxone (0.4 mg/kg i.v.), significantly enhanced the slope of the CO2 response curve for VEq (20 +/- 3 mmHg.min-1.%CO2-1) compared with the control (14 +/- 2 mmHg.min-1.%CO2(-1)) (P < 0.05; n = 14). A similar enhancement of the hypercapnic response by naloxone was found in rats anaesthetised with urethane (n = 5). The mu receptor agonist dermorphin (1 mg/kg i.v.) significantly depressed the slope of the CO2 response curve for IEP (-0.01 +/- 0.03) compared with the control (0.10 +/- 0.03) in pentobarbital anaesthetised rats (P < 0.05; n = 5) but had no significant effect on respiratory rate. These results suggest a role of endogenous opioids in the modulation of respiration during hypercapnia.
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Affiliation(s)
- K R Eager
- School of Biological Sciences, Victoria University of Wellington, New Zealand
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216
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217
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Ranalexin. A novel antimicrobial peptide from bullfrog (Rana catesbeiana) skin, structurally related to the bacterial antibiotic, polymyxin. J Biol Chem 1994. [DOI: 10.1016/s0021-9258(17)34136-4] [Citation(s) in RCA: 160] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
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218
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Affiliation(s)
- V Mutt
- Department of Biochemistry II, Karolinska Institute, Stockholm, Sweden
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219
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Charpentier S, Sagan S, Naim M, Delfour A, Nicolas P. Mechanism of delta-opioid receptor selection by the address domain of dermenkephalin. Eur J Pharmacol 1994; 266:175-80. [PMID: 8157070 DOI: 10.1016/0922-4106(94)90107-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Dermenkephalin (Tyr-D-Met-Phe-His-Leu-Met-AspNH2) is a highly potent and selective delta-opioid peptide isolated from frog skin. It was recently recognized that the C-terminus His4-Leu5-Met6-Asp7NH2 of dermenkephalin was responsible for the addressing of the peptide towards the delta-opioid receptor. In order to investigate the role played by residues 4, 5 and 6 in this 'delta address', we synthesized and evaluated 20 new analogues for their ability to displace tritiated ligands from mu- and delta-opioid sites. Results showed that position 4 of dermenkephalin contributes to delta selectivity independently of delta-opioid receptor binding by preventing a high affinity mu binding. Position 5 requires a hydrophobic side chain to enhance delta affinity. A high delta affinity was obtained with any amino acids introduced in position 6 suggesting that residue 6 serves as a neutral spacer. Thus, the main features responsible for the high delta-opioid selectivity of dermenkephalin are electrostatic repulsions with the mu-opioid receptor, additional hydrophobic interactions with the delta-opioid receptor and folding of the C-terminal domain.
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Affiliation(s)
- S Charpentier
- Laboratoire de Bioactivation des Peptides, Institut Jacques Monod, Université Paris, France
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220
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Barra D, Mignogna G, Simmaco M, Pucci P, Severini C, Falconieri-Erspamer G, Negri L, Erspamer V. [D-Leu2]deltorphin, a 17 amino acid opioid peptide from the skin of the Brazilian hylid frog, Phyllomedusa burmeisteri. Peptides 1994; 15:199-202. [PMID: 8008623 DOI: 10.1016/0196-9781(94)90002-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
A novel 17 amino acid peptide, having a D-leucine in position 2 of its sequence, has been isolated from methanol extracts of the skin of the Brazilian frog, Phyllomedusa burmeisteri. The sequence of the peptide is: Tyr-D-Leu-Phe-Ala-Asp-Val-Ser-Thr-Ile-Gly-Asp-Phe-Phe-His-Ser-Ile-NH2. It displays a poor affinity for delta-opioid binding sites, both in the periphery and in the central nervous system. However, the shorter synthetic amidated analogue (1-10) possess both on the central and peripheral delta binding sites an agonistic potency equalling in affinity and exceeding in selectivity that of the enkephalins. The shorter amidated analogue (1-7) is virtually inactive on opioid binding sites in the periphery, but displays a clear-cut affinity for both delta and mu binding sites on rat brain membranes. To date six different D-amino acid residues have been found, always in position 2 of the sequence, in as many as 11 natural peptide molecules of animal origin.
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Affiliation(s)
- D Barra
- Dipartimento di Scienze Biochimiche, Università La Sapienza, Roma, Italy
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221
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Prerequisite for His4 in deltorphin A for high? opioid receptor selectivity. Amino Acids 1994; 7:291-304. [DOI: 10.1007/bf00807704] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/1993] [Accepted: 09/20/1993] [Indexed: 10/26/2022]
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222
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Attila M, Salvadori S, Balboni G, Bryant SD, Lazarus LH. Synthesis and receptor binding analysis of dermorphin hepta-, hexa- and pentapeptide analogues. Evidence for one- and two-side binding models for the mu-opioid receptor. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1993; 42:550-9. [PMID: 7905867 DOI: 10.1111/j.1399-3011.1993.tb00363.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Sixteen dermorphin analogues were synthesized and characterized for mu- and delta-opioid receptor binding properties using [3H]DAGO and [3H]DPDPE, respectively. The analogues included the following: substitutions at position 4 and/or the C-terminal residue; deletions of Gly4 or Pro6-Ser7; inclusion of Z or an acetyl group on the epsilon-amino group of Lys7; and the presence of either a C-terminal amide or free acid group. Two peptides, [Lys7-OH]- and [Lys7-NH2]dermorphin, had mu-affinities (Ki mu = 0.15-0.13 nM) and mu-selectivities (Ki delta/Ki mu = 1158-1482) higher than dermorphin (Ki mu = 0.28 nM; Ki delta/Ki mu = 295) and best fitted a one-site binding model similar to dermorphin. Significantly better (P < 0.0001) fits to a two-site binding model vs. a one-site model were observed with four dermorphin analogues: [Lys(Z)7-OH]heptapeptide, [des-Gly4(Tyr4,Pro5,Asn6-OH)]hexapeptide and two pentapeptides, [Tyr5-NH2] and [Trp4,Asn5-OH]. Our data revealed a complex binding pattern for dermorphin analogues to brain mu-receptors in which Hill coefficients less than 0.85 generally suggest heterogeneity of mu-receptors; however, only detailed analyses of the data derived from the non-linear regression fits for one- or two-components gave evidence for the possible existence of two separate [3H]DAGO binding sites. Eight of our dermorphin analogues had significantly better fits for a two-site model (P < 0.05), but only four seemed to have two distinct Ki values (P < 0.0001).
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Affiliation(s)
- M Attila
- National Institute of Environmental Health Sciences, Laboratory of Integrative Biology, Research Triangle Park, North Carolina
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223
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Naim M, Charpentier S, Nicolas P, Baron D. Quantitative two-dimensional NMR study of dermenkephalin, a highly potent and selective delta-opioid peptide. Biopolymers 1993; 33:1889-900. [PMID: 8268413 DOI: 10.1002/bip.360331214] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Dermenkephalin, H-Tyr-(D)Met-Phe-His-Leu-Met-Asp-NH2, a highly potent and selective delta-opioid peptide isolated from frog skin, was studied in DMSO-d6 solution by two-dimensional nmr spectroscopy, including the determination of NH temperature coefficients, the evaluation of 3J coupling constants from phase-sensitive correlated spectroscopy (COSY) and the volumes of nuclear Overhauser effect (NOE) correlations. The two-dimensional NOE spectroscopy (NOESY) spectrum of dermenkephalin revealed sequential, medium-, and long-range effects. To put this information on a quantitative basis, special attention was devoted to J cross-peak suppression, quantification of the NOE volumes and analysis of the overlaps, normalization of the NOEs against diagonal peaks and H beta beta' geminal interactions. Although most of the dihedral angles deduced from the 3JN alpha coupling constants together with several Ni alpha i and alpha iNi+1 NOEs pointed to a partially extended peptide backbone, several NiNi+1 NOEs and beta iNi+1 interactions argued in favor of a folded structure. Moreover, several long-range correlations of strong intensities were found that supported a close spatial proximity between the side chains of D-Met2 and Met6, Tyr1 and His4, Tyr1 and Asp7, and His4 and the C-terminal amide group. In Phe, the g- rotamer in the side chain is deduced from the 3J alpha beta coupling constants and alpha beta and N beta NOE correlations. Whereas the amide proton dependency was not indicative of stable hydrogen bonds, the nonuniform values of the temperature coefficient may reflect an equilibrium mixture of folded and extended conformers. The overall data should provide realistic starting models for energy minimization and modelization studies.
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Affiliation(s)
- M Naim
- Laboratoire de Bioactivation des Peptides, Université Paris 7, France
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224
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Agerberth B, Boman A, Andersson M, Jörnvall H, Mutt V, Boman HG. Isolation of three antibacterial peptides from pig intestine: gastric inhibitory polypeptide (7-42), diazepam-binding inhibitor (32-86) and a novel factor, peptide 3910. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 216:623-9. [PMID: 8375398 DOI: 10.1111/j.1432-1033.1993.tb18182.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Two antibacterial peptides, cecropin P1 and PR-39 (39-residue proline/arginine-rich peptide), from the upper part of pig small intestine have previously been isolated and characterized. We have now continued our search for antibacterial peptides in different side fractions generated during the isolation of intestinal hormones. Starting from one such fraction and monitoring activity against Bacillus megaterium, we isolated three homogeneous peptides by three consecutive chromatographic steps. Amino acid sequence analysis in combination with mass spectrometry identified two of the peptides as gastric inhibitory polypeptide (7-42) [GIP(7-42)] and diazepam-binding inhibitor (32-86) [DBI(32-86)], derived from factors already known. However, intact GIP and DBI have hardly any antibacterial activity by themselves. The third peptide constitutes a previously unknown structure, designated as peptide 3910 from its molecular mass. All three peptides showed good activity against B. megaterium. In addition, GIP (7-42) showed some activity against Streptococcus pyogenes and an Escherichia coli mutant with a defect in its outer membrane.
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Affiliation(s)
- B Agerberth
- Department of Biochemistry II, Karolinska Institutet, Stockholm, Sweden
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225
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Seethaler G, Le Caer JP, Rossier J, Kreil G. Frog prodermorphin expressed in mammalian cells is partly converted to the hydroxyproline containing precursor. Neuropeptides 1993; 25:61-4. [PMID: 8413852 DOI: 10.1016/0143-4179(93)90070-q] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Using recombinant vaccinia virus, we have expressed in mammalian cells the cDNA coding for the precursor of dermorphin, a D-alanine containing opioid peptide from the skin of the South American frog Phyllomedusa sauvagei. HeLa cells and AtT-20 cells produced prodermorphin where proline-6 of dermorphin was partly hydroxylated. This was demonstrated by digesting the partially purified precursors with trypsin and carboxypeptidase B. After immunoprecipitation and separation by HPLC, two decapeptides were detected which differed by the presence of proline or hydroxy-proline at position 6. This demonstrates that HeLa cells as well as AtT-20 cells can perform the post-translational conversion of certain proline residues to hydroxyproline in a foreign hormone precursor expressed in these cells.
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Affiliation(s)
- G Seethaler
- Institute of Molecular Biology, Austrian Academy of Sciences, Salzburg
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226
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Sakurada S, Nakata N, Sakurada T, Chaki K, Kawamura S, Kisara K, Suzuki K. Tolerance and cross-tolerance to the antinociceptive effects of [D-Arg2]-dermorphin tetrapeptide analogue and morphine. Neuropharmacology 1993; 32:689-93. [PMID: 8361582 DOI: 10.1016/0028-3908(93)90082-e] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Rats were given repeated subcutaneous injections of [D-Arg2, Sar4]-dermorphin (1-4) [DAS-DER-(1-4)] and/or morphine over a period of 4 or 7 days. Antinociception was determined at 90 min for DAS-DER (1-4) and 30 min for morphine after each morning injection (9:00 a.m.), using the tail-flick and digit pinching tests in rats. Subcutaneous administration of DAS-DER (1-4) and morphine produced the development of antinociceptive tolerance, respectively. A marked tolerance to DAS-DER (1-4) and morphine was seen in rats made tolerant to morphine. However, administration of morphine produced no significant decrement in the antinociceptive activity in rats made tolerant to DAS-DER (1-4). These results suggest that the site of action of DAS-DER (1-4) may be more limited than that of morphine in the nociceptive pathways, for lack of its antinociceptive efficacy in morphine-tolerant rats.
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Affiliation(s)
- S Sakurada
- Department of Pharmacology, Tohoku College of Pharmacy, Sendai, Japan
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227
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Guis C, Bruetschy L, Meudal H, Roques BP, Gacel GA. Investigation of the structural parameters involved in the delta-opioid selectivity of several families of opioid peptides. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1993; 41:576-86. [PMID: 8394291 DOI: 10.1111/j.1399-3011.1993.tb00480.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Three series of highly delta-opioid selective peptides are now available, and each family is used as template to investigate the structural parameters involved in delta-receptor recognition and in the modulation of the selectivity of the parent peptide. The first series includes cyclic derivatives such as Tyr-D-Pen-Gly-Phe-D-Pen(DPDPE) and Tyr-D-Pen-Gly-Phe-Pen(DPLPE); the second are the synthetic linear constrained peptides [Tyr-D-Ser(OtBu)-Gly-Phe-Leu-Thr(DSTBULET), Tyr-D-Ser(OtBu)-Gly-Phe-Leu-Thr (OtBu)(BUBU) and especially Tyr-D-Cys(StBu)-Gly-Phe-Leu-Thr(OtBu) (BUBUC)] and the last one the natural peptides [Tyr-D-Met-Phe-His-Leu-Met-Asp-NH2 (deltorphin or dermenkephalin) and Tyr-D-Ala-Phe-Asp-Val-Val-GlyNH2 ([D-Ala2] deltorphin I)]. In the present study, the possibly of transposing some of the decisive factors of delta-selectivity evidenced in the two other families, to the linear constrained peptides series was examined. With this aim in view, residues such as Phe3, pClPhe4 or Asp were introduced in the sequence of DSTBULET, BUBU or BUBUC. Direct comparison between the biochemical profiles of the [pClPhe4] analogs of the linear constrained peptides and their parent compounds shows that the addition of an electronegative atom on the Phe4 residue of enkephalin sequences is not an absolute parameter for delta-selectivity improvement. The hydrophobic delta-receptor subsite seems able to receive a range of molecular volumes and electronegativities. By contrast, this subsite cannot interact with a Phe3 aromatic ring introduced in this series of peptides. Moreover, the results obtained with linear peptides including additional negatively charged residues demonstrate that the proposed location of the delta-receptors in a cationic membrane environment is not adequate to explain the selectivity profile of a number of compounds.
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Affiliation(s)
- C Guis
- Department of Molecular and Structural Pharmacochemistry, U266 INSERM-URAD 1500 CNRS, René Descartes University, Paris, France
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228
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Paakkari P, Paakkari I, Landes P, Sirén AL, Feuerstein G. Respiratory mu-opioid and benzodiazepine interactions in the unrestrained rat. Neuropharmacology 1993; 32:323-9. [PMID: 8098861 DOI: 10.1016/0028-3908(93)90152-s] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Interactions of mu-opioid receptors with the benzodiazepine system were studied by examining the modulatory effects of flumazenil (a benzodiazepine antagonist) and alprazolam (a benzodiazepine agonist) on the respiratory effects of the opioid peptide dermorphin. Dermorphin, 1-30 nmol administered i.c.v., to conscious, unrestrained rats decreased ventilation rate (VR) and minute volume (MV) dose-dependently. The ventilatory depression was antagonized by naloxone and by the benzodiazepine antagonist flumazenil. The benzodiazepine alprazolam potentiated the respiratory inhibition of a small (1 nmol) dose of dermorphin but antagonized that of a higher dose (3 nmol). The results suggest that the benzodiazepine/GABA receptor complex modulates respiratory depression induced by central mu-receptor stimulation in the rat.
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Affiliation(s)
- P Paakkari
- Department of Neurology, Uniformed Services University of the Health Sciences, Bethesda, MD 20184
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229
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Ohno Y, Segawa M, Ohishi H, Doi M, Kitamura K, Ishida T, Inoue M, Iwashita T. Conformation of deltorphin-II in membrane environment studied by two-dimensional NMR spectroscopy and molecular dynamics calculations. EUROPEAN JOURNAL OF BIOCHEMISTRY 1993; 212:185-91. [PMID: 8383038 DOI: 10.1111/j.1432-1033.1993.tb17649.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Two-dimensional homonuclear Hartmann-Hahn spectroscopy and NOESY (nuclear Overhauser effect and exchange spectroscopy) 1H-NMR techniques have been used to obtain complete proton resonance assignments and to perform a conformational investigation of deltorphin-II (Tyr-D-Ala-Phe-Glu-Val-Val-Gly-NH2), a naturally occurring delta-selective opioid peptide, in the membrane-mimetic micelles of perdeuterated dodecylphosphocholine. This was done in order to examine conformational characteristics that would be closely related to the selectivity towards the delta-opioid receptor. With the use of the proton-proton distances derived from NOESY measurements, 50 possible three-dimensional structures were generated by means of distance-geometry calculations, and 25 of them were subjected to the molecular-dynamics simulations of 10 ps, which were energetically constrained for the NOE interproton distances. Most of the possible conformers simulated showed a common feature such that the conformation of deltorphin-II is characterized by the S-shaped back-bone structure in which the turn conformation of the Val-Val-Gly-NH2 sequence is located under the helically folded conformation of the N-terminal Tyr-D-Ala-Phe-Glu sequence. The possible relationship between this conformational characteristic and the delta-opioid-receptor selectivity has been discussed.
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Affiliation(s)
- Y Ohno
- Department of Physical Chemistry, Osaka University of Pharmaceutical Sciences, Japan
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230
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Fujisawa Y, Ikeda T, Nomoto K, Yasuda-Kamatani Y, Minakata H, Kenny PT, Kubota I, Muneoka Y. The FMRFamide-related decapeptide of Mytilus contains a D-amino acid residue. ACTA ACUST UNITED AC 1992; 102:91-5. [PMID: 1358533 DOI: 10.1016/0742-8413(92)90049-d] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
1. An FMRFamide-related decapeptide isolated from the anterior byssus retractor muscle (ABRM) of the bivalve mollusc, Mytilus edulis, was shown to have D-Leu as the second amino acid residue. 2. The excitatory effects of the peptide (Mytilus-FFRFamide) on the ABRM were not changed appreciably by substituting an L-Leu residue for the D-Leu residue.
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Affiliation(s)
- Y Fujisawa
- Faculty of Integrated Arts and Sciences, Hiroshima University, Japan
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231
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Mor A, Amiche M, Nicolas P. Enter a new post-translational modification: D-amino acids in gene-encoded peptides. Trends Biochem Sci 1992; 17:481-5. [PMID: 1471255 DOI: 10.1016/0968-0004(92)90333-5] [Citation(s) in RCA: 52] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The post-translational processing of peptides plays a key role in conferring biological activity on those peptides. Recently, ribosomally made peptides that contain D-amino acids at specific positions have been discovered in microorganisms as well as in vertebrates and invertebrates. This points to yet another strategy of circumventing stereochemical limitations imposed by the genetic code and conveying biological activity to otherwise inert molecules.
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Affiliation(s)
- A Mor
- Laboratoire de Bioactivation des Peptides, Institut Jacques Monod, Université Paris, France
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232
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Lazarus LH, Salvadori S, Grieco P, Wilson WE, Tomatis R. Unique sequence in deltorphin C confers structural requirement for δ opioid receptor selectivity. Eur J Med Chem 1992. [DOI: 10.1016/0223-5234(92)90113-f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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233
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Nagata Y, Masui R, Akino T. The presence of free D-serine, D-alanine and D-proline in human plasma. EXPERIENTIA 1992; 48:986-8. [PMID: 1426150 DOI: 10.1007/bf01919147] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Twelve neutral free amino acids, i.e. serine, threonine, glutamine, asparagine, alanine, proline, methionine, tyrosine, valine, leucine, isoleucine and phenylalanine, were surveyed for the presence of D-enantiomers in plasma samples from patients with renal diseases and from normal subjects. D-serine, D-alanine and D-proline were found in the patient's plasma. The highest concentrations (D/L ratio) of D-serine, D-alanine and D-proline were 0.2362, 0.2087 and 0.0986, respectively. The sum of the contents of the three D-amino acid was shown to be present in the plasma proteins.
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Affiliation(s)
- Y Nagata
- Department of Life Science, Himeji Institute of Technology, Japan
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234
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Sagan S, Charpentier S, Delfour A, Amiche M, Nicolas P. The aspartic acid in deltorphin I and dermenkephalin promotes targeting to delta-opioid receptor independently of receptor binding. Biochem Biophys Res Commun 1992; 187:1203-10. [PMID: 1329732 DOI: 10.1016/0006-291x(92)90431-j] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Recent studies on the highly potent and selective delta-opioid agonists demenkephalin (Tyr-D-Met-Phe-His-Leu-Met-Asp-NH2) and deltorphin I (Tyr-D-Ala-Phe-Asp-Val-Val-Gly-NH2) suggested that key structural features necessary for specific targetting to the delta-opioid receptor are located within the C-terminal halves of these naturally occurring heptapeptides. To investigate the contribution of aspartic acid 4 residue in deltorphin I and aspartic acid 7 residue in dermenkephalin to the delta-addressing ability of the C-terminal ends, fourteen analogs were synthesized and assessed for their ability to bind to mu and delta-opioid receptors in rat brain membrane homogenates. Results showed that i/ although the tetrapeptide C-terminus of dermenkephalin and deltorphin I differ in amino acid composition, they play a similar role in specifying correct addressing of these peptides to the delta-receptor, ii/ the negatively charged side chain of aspartic acid 4 residue in deltorphin I and aspartic acid 7 residue in dermenkephalin is not involved in binding contact at the delta-receptor site, nor in maintaining a delta-bioactive folding of the peptides, iii/ these side chains are, in contrast, functionally or structurally required to confer high delta-selectivity by preventing mu-site recognition and/or binding.
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Affiliation(s)
- S Sagan
- Laboratoire de Bioactivation des Peptides, Institut Jacques Monod, Université Paris 7, France
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235
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Bawab W, Querido E, Crine P, DesGroseillers L. Identification and characterization of aminopeptidases from Aplysia californica. Biochem J 1992; 286 ( Pt 3):967-75. [PMID: 1417757 PMCID: PMC1132997 DOI: 10.1042/bj2860967] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Aminopeptidase activities were identified in extracts of kidney, ovotestis, head ganglia, heart and haemolymph of Aplysia californica. These enzyme preparations hydrolysed [3H][Leu]enkephalin at the Try-1-Gly-2 bond as determined by h.p.l.c. analysis of cleavage products. In all these tissues, enkephalin-degrading aminopeptidase activities were present both in membrane-bound and cytosolic fractions. The bivalent-cation-chelating agent, 1,10-phenanthroline, inhibited kidney membrane aminopeptidase activity with an IC50 of 30 microM, suggesting that this enzyme is a metalloproteinase. The aminopeptidase inhibitor amastatin was the most potent inhibitor of [Leu]enkephalin degradation (IC50 25 nM) by membrane-bound aminopeptidase, and bacitracin, bestatin and puromycin were about 100-1000 times less potent. In contrast with membrane-bound aminopeptidase, the cytosolic form is sensitive to puromycin. Angiotensin-converting enzyme inhibitor had no effect on [Leu]enkephalin degradation by kidney membranes, while the neutral endopeptidase inhibitors were poor inhibitors of the enzymes in this preparation. The Km values of the aminopeptidase in the kidney membranes and cytosolic fractions for the [Leu]enkephalin substrate were 2.4 and 7.4 microM respectively. The aminopeptidase present in the kidney membranes also hydrolysed endogenous Phe-Met-Arg-Phe-amide peptide at the Phe-1-Met-2 bond as well as synthetic alanine p-nitroanilide and leucine p-nitroanilide. When used in a competition assay, these substrates inhibited hydrolysis of [3H][Leu]enkephalin, suggesting that the same enzyme degraded all these substrates. Taken together, these results suggest that Aplysia tissues contain both a membrane-bound aminopeptidase related to the mammalian aminopeptidase N and a cytosolic puromycin-sensitive aminopeptidase.
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Affiliation(s)
- W Bawab
- Department of Biochemistry, University of Montreal, Quebec, Canada
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236
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Negri L, Erspamer GF, Severini C, Potenza RL, Melchiorri P, Erspamer V. Dermorphin-related peptides from the skin of Phyllomedusa bicolor and their amidated analogs activate two mu opioid receptor subtypes that modulate antinociception and catalepsy in the rat. Proc Natl Acad Sci U S A 1992; 89:7203-7. [PMID: 1353890 PMCID: PMC49674 DOI: 10.1073/pnas.89.15.7203] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Three naturally occurring dermorphin-like peptides from the skin of the frog Phyllomedusa bicolor, the related carboxyl-terminal amides, and some substituted analogs were synthesized, their binding profiles to opioid receptors were determined, and their biological activities were studied in isolated organ preparations and intact animals. The opioid binding profile revealed a very high selectivity of these peptides for mu sites and suggested the existence of two receptor subtypes, of high and low affinity. The peptides tested acted as potent mu opioid agonists on isolated organ preparations. They were several times more active in inhibiting electrically evoked contractions in guinea pig ileum than in mouse vas deferens. When injected into the lateral brain ventricle or peritoneum of rats, the high-affinity-site-preferring ligand, [Lys7-NH2]dermorphin, behaved as a potent analgesic agent. By contrast, the low-affinity-site-preferring ligand, [Trp4,Asn7-NH2]dermorphin, produced a weak antinociception but an intense catalepsy.
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MESH Headings
- Amino Acid Sequence
- Analgesics, Opioid/pharmacology
- Animals
- Anura
- Binding, Competitive
- Brain/metabolism
- Catalepsy/physiopathology
- Cerebral Ventricles/drug effects
- Cerebral Ventricles/physiology
- Electric Stimulation
- Enkephalin, Ala(2)-MePhe(4)-Gly(5)-
- Enkephalins/metabolism
- Guinea Pigs
- Injections, Intraventricular
- Kinetics
- Molecular Sequence Data
- Myenteric Plexus/drug effects
- Myenteric Plexus/physiology
- Naloxone/pharmacology
- Nociceptors/physiology
- Oligopeptides/administration & dosage
- Oligopeptides/isolation & purification
- Oligopeptides/pharmacology
- Opioid Peptides
- Pain/physiopathology
- Rats
- Receptors, Opioid/drug effects
- Receptors, Opioid/metabolism
- Receptors, Opioid/physiology
- Receptors, Opioid, delta
- Receptors, Opioid, kappa
- Receptors, Opioid, mu
- Skin/chemistry
- Skin Physiological Phenomena
- Structure-Activity Relationship
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Affiliation(s)
- L Negri
- Institute of Pharmacology, University La Sapienza, Rome, Italy
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237
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Erspamer GF, Severini C. Guinea-pig ileum (GPI) and mouse vas deferens (MVD) preparations in the discovery, discrimination and parallel bioassay of opioid peptides. Pharmacol Res 1992; 26:109-21. [PMID: 1329062 DOI: 10.1016/s1043-6618(05)80124-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
As many as 47 amphibian and mammalian, natural and non-natural opioid peptides have been examined in guinea-pig ileum (GPI) and mouse vas deferens (MVD) preparations. The great value of these extremely simple and accessible tissue models in the identification, isolation and purification of endogenous opioid peptides, in studying structure/activity relationships, and in determining selectivity of the peptide molecules for the various opioid receptors, especially delta- and mu-receptors, is emphasized.
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Affiliation(s)
- G F Erspamer
- Institute of Medical Pharmacology III, University of Rome La Sapienza, Italy
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238
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Muneoka Y, Kobayashi M. Comparative aspects of structure and action of molluscan neuropeptides. EXPERIENTIA 1992; 48:448-56. [PMID: 1601109 DOI: 10.1007/bf01928163] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A number of neuropeptides were isolated from the ganglia and muscles of molluscs, and their actions were examined. Diverse neuropeptides, in addition to several classical neurotransmitters, were suggested to be involved in the regulation of the anterior byssus retractor muscle of Mytilus. A wide structural variety of members of the Mytilus inhibitory peptide family was observed in each of the genera Mytilus, Achatina and Helix. Gly-Trp-NH2, the C-terminal dipeptide fragment of the neuropeptide AGPWamide, showed a more potent action than the parent peptide in all of the muscles examined. Peptides related to some molluscan neuropeptides were found to be distributed interphyletically. Some neuropeptides containing a D-amino acid residue were found in Achatina and Mytilus. These aspects of molluscan neuropeptides are thought not to be exceptional.
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Affiliation(s)
- Y Muneoka
- Physiological Laboratory, Faculty of Integrated Arts and Sciences, Hiroshima University, Japan
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239
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Heyl DL, Mosberg HI. Modification of the Phe3 aromatic moiety in delta receptor-selective dermorphin/deltorphin-related tetrapeptides. Effects on opioid receptor binding. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1992; 39:450-7. [PMID: 1330964 DOI: 10.1111/j.1399-3011.1992.tb01449.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
The previously described cyclic delta opioid receptor-selective tetrapeptide H-Tyr-D-Cys-Phe-D-Pen-OH (JOM-13) was modified at residue 3 by incorporation of both natural and unnatural amino acids with varying steric, electronic, and lipophilic properties. Effects on mu and delta opioid receptor binding affinities were evaluated by testing the compounds for displacement of radiolabeled receptor-selective ligands in a guinea pig brain receptor binding assay. Results obtained with the bulky aromatic 1-Nal3 and 2-Nal3 substitutions suggest that the shape of the receptor subsite with which the side chain of the internal aromatic residue interacts differs for delta and mu receptors. This subsite of either receptor can accommodate the transverse steric bulk of the 1-Nal3 side chain but only the delta receptor can readily accept the more elongated 2-Nal3 side chain. Several analogs with pi-excessive heteroaromatic side chains in residue 3 were examined. In general, these analogs display diminished binding to mu and delta receptors, consistent with previous findings for analogs with residue 3 substitutions of modified electronic character. Several analogs with alkyl side chains in residue 3 were also examined. While delta receptor binding affinity is severely diminished with Val3, Ile3, and Leu3 substitutions, Cha3 substitution is very well tolerated, indicating that, contrary to the widely held belief, an aromatic side chain in this portion of the ligand is not required for delta receptor binding. Where possible, comparison of results in this delta-selective tetrapeptide series with those reported for analogous modification in the cyclic delta-selective pentapeptide [D-Pen2, D-Pen5]enkephalin (DPDPE) and linear pentapeptide enkephalins reveals similar trends.
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Affiliation(s)
- D L Heyl
- College of Pharmacy, University of Michigan, Ann Arbor
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240
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Coffey AF, Johnson T. Continuous flow solid (gel) phase peptide synthesis using unsupported ultra-high load polymers. INTERNATIONAL JOURNAL OF PEPTIDE AND PROTEIN RESEARCH 1992; 39:419-30. [PMID: 1428532 DOI: 10.1111/j.1399-3011.1992.tb01446.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
A simple, manually operated, continuous flow apparatus is described for solid (gel) phase peptide synthesis. The approach uses an unsupported phenolic bead form core network at an initial matrix loading of 5 mmol g-1, the theoretical maximum. The synthesis is performed in a flow reactor under low pressure conditions. "Layered displacement" of reagent solutions and washing solvents is an essential feature that has been developed to facilitate efficient peptide synthesis. The usefulness of the present system in conjunction with N alpha Boc protected amino acids is illustrated by the syntheses of [Leu5]-enkephalin and dermorphin. The potential for scale up synthesis has also been investigated.
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Affiliation(s)
- A F Coffey
- School of Applied Sciences, Wolverhampton Polytechnic, UK
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241
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Sato T, Sakurada S, Sakurada T, Kisara K, Suzuki K. Comparison of opioid properties between d-arg-containing dipeptides and tetrapeptides. Biochem Pharmacol 1992; 43:717-23. [PMID: 1347216 DOI: 10.1016/0006-2952(92)90235-b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Since the D-Arg-containing dipeptides, H-Tyr-D-Arg-OMe (TDA) and H-Tyr(Et)-D-Arg-OMe, and D-Arg2-substituted dermorphin N-terminal tetrapeptide analogues, H-Tyr-D-Arg-Phe-Gly-OEt (TDAPG) and H-Tyr(Et)-D-Arg-Phe-Gly-OEt gave different pharmacological responses in vivo, opioid interaction and structure-activity relationships have been investigated in vitro. In the isolated guinea-pig ileum assay, the tetrapeptides were potently inhibitory, their activity markedly exceeding that of the dipeptides. In particular, the first tetrapeptide had twice the activity of morphine, while the potency of the dipeptides was less than one twentieth that of morphine. Also in the opioid receptor binding assay, tetrapeptides had a higher affinity than the dipeptides. IC50 values of tetrapeptides were 8.46 and 23.7 nM, respectively, which were lower than that of morphine. Ethylation of the Tyr residue of TDA much increased the opioid activity whereas that of TDAPG greatly decreased it. All peptides used were extremely stable to aminopeptidase-M and carboxypeptidase-Y and had an inhibitory effect on enkephalin (EK)-degrading enzymes. From these results, it appears that the effects of the tetrapeptides are due mainly to specific interaction with opioid receptors, whereas the dipeptides do not act specifically on the opioid receptors, but are involved in non-opioid mechanisms. The resistance to enzymes and inhibitory effect of the peptides used on the EK-degrading enzymes may also account for their potent and long-lasting opioid-like activities.
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Affiliation(s)
- T Sato
- Department of Pharmaceutics, Tohoku College of Pharmacy, Sendai, Japan
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242
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Affiliation(s)
- V Erspamer
- Institute of Medical Pharmacology III, University La Sapienza, Città Universitaria, Rome, Italy
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243
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Schmidt R, Neubert K, Barth A, Liebmann C, Schnittler M, Chung NN, Schiller PW. Structure-activity relationships of cyclic beta-casomorphin-5 analogues. Peptides 1991; 12:1175-80. [PMID: 1667685 DOI: 10.1016/0196-9781(91)90191-q] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Cyclic analogues of the beta-casein-derived opioid peptide beta-casomorphin-5 (H-Tyr-Pro-Phe-Pro-Gly-OH) were prepared through substitution of the Pro2 residue with various alpha,omega-diamino acid residues (lysine, ornithine, 2,4-diaminobutyric acid) and cyclization of the omega-amino group to the C-terminal carboxyl function. Compounds of this type, with D-configuration at the 2-position residue, showed high opioid receptor affinity with some preference for mu receptors over delta receptors, high potency in the guinea pig ileum assay and considerable activity in the mouse vas deferens assay. Configurational inversion at the 4-position in these cyclic analogues resulted in enhanced affinity for both mu and delta receptors, whereas N-methylation of the Phe3 residue produced a potency decrease.
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Affiliation(s)
- R Schmidt
- Department of Biotechnology, Martin-Luther University Halle, FRG
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244
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Sasaki Y, Ambo A, Suzuki K. [D-Ala2]deltorphin II analogs with high affinity and selectivity for delta-opioid receptor. Biochem Biophys Res Commun 1991; 180:822-7. [PMID: 1659404 DOI: 10.1016/s0006-291x(05)81138-6] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Nine [D-Ala2]deltorphin II (DL-II:Tyr-D-Ala-Phe-Glu-Val-Val-Gly-NH2) analogs having various aliphatic amino acids at positions 5 and 6 were synthesized to gain more information about the role of hydrophobic Val5,6 residues for the delta-opioid receptor selectivity. Binding assays of analogs replaced by Ala demonstrated the importance of hydrophobic Val5,6 residues in DL-II for delta-affinity and selectivity, and especially critical importance of Val5 residue for higher delta-selectivity. By enhancing the hydrophobicity of residues at positions 5 and 6, we have developed analogs with very high delta-affinity and selectivity over those of DL-II, e.g., [Ile5,6], [norleucine5,6] and [gamma-methyl-leucine5,6]DL-II, which will be useful as delta-selective ligands for investigation of the physiological role of opioid receptors.
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Affiliation(s)
- Y Sasaki
- Tohoku College of Pharmacy, Sendai, Japan
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245
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Sagan S, Corbett AD, Amiche M, Delfour A, Nicolas P, Kosterlitz HW. Opioid activity of dermenkephalin analogues in the guinea-pig myenteric plexus and the hamster vas deferens. Br J Pharmacol 1991; 104:428-32. [PMID: 1665735 PMCID: PMC1908574 DOI: 10.1111/j.1476-5381.1991.tb12446.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
1. To elucidate the structural features required for selective and potent action of dermenkephalin at the delta-opioid receptor, a series of analogues of dermenkephalin and dermorphin were tested for their effectiveness in depressing electrically-evoked contractions of the vas deferens of the hamster (delta-opioid receptors) and the guinea-pig myenteric plexus-longitudinal muscle preparation (mu- and kappa-opioid receptors). 2. Dermenkephalin was more selective and more potent at delta-receptors than the delta-ligand [D-Pen2, D-Pen5]-enkephalin. The responses to dermenkephalin in the hamster vas deferens were increased by addition of peptidase inhibitors; the maximum effect was obtained with 3 microM thiorphan. 3. [L-Met2]-dermenkephalin had 0.2% and [L-Ala2]-dermorphin 0.01% of the agonist activity of the corresponding endogenous peptides which have D-amino acids in position 2. The pharmacological activity of these analogues was unaffected by inhibition of peptidases. This emphasizes the role that the D-configuration plays in determining the bioactive folding of these highly active peptides. 4. Dermenkephalin-(1-6)-NH2 was more potent at delta-receptors than at mu-receptors whereas, dermenkephalin-(1-4)-NH2 is a selective mu-agonist, having no activity at delta-receptors. 5. Substitution of the C-terminal tripeptide of dermorphin with the C-terminal tripeptide of dermenkephalin abolished the mu-receptor preference of dermorphin. The resulting hybrid peptide, Tyr-D-Ala-Phe-Gly-Leu-Met-Asp-NH2 was as potent as dermenkephalin at delta-receptors. A shift towards a preference for delta-receptors was obtained when the C-terminal tetrapeptide of dermorphin was replaced by the C-terminal tetrapeptide of dermenkephalin. 6. Substitution of Asp by Asn in position 7 of dermenkephalin caused an increase in mu-receptor potency and a decrease in delta-receptor potency, resulting in a 20 fold decrease in mu-receptor selectivity. Dermenkephalin-(1-6)-NH2 and [Asn7]-dermenkephalin have almost identical delta-receptor agonist potencies and ratios of IC50 in the myenteric plexus to IC50 in the hamster vas deferens. 7. The results obtained emphasise the importance of a negative charge at the C-terminus of dermenkephalin for selectivity at the delta-opioid receptor. Furthermore, the hydrophobic residues Leu5 and Met6 may be critical in ensuring tight binding to the receptor which results in high agonist potency.
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Affiliation(s)
- S Sagan
- Laboratoire de Bioactivation des Peptides, Institut Jacques Monod, Université Paris 7, France
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246
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Charpentier S, Sagan S, Delfour A, Nicolas P. Dermenkephalin and deltorphin I reveal similarities within ligand-binding domains of mu- and delta-opioid receptors and an additional address subsite on the delta-receptor. Biochem Biophys Res Commun 1991; 179:1161-8. [PMID: 1656944 DOI: 10.1016/0006-291x(91)91693-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Dermorphin (Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2), dermenkephalin (Tyr-D-Met-Phe-His-Leu-Met-Asp-NH2) and deltorphin I (Tyr-D-Ala-Phe-Asp-Val-Val-Gly-NH2) are the first naturally occurring peptides highly potent for and almost specific to the mu- and delta-opioid receptors, respectively. The amino-terminal domains Tyr-D-X-Phe (where X is either Ala or Met) of these peptides behave as selective and potent mu-receptor ligands. Routing of Tyr-D-X-Phe to the delta- or the mu- receptor is associated with the presence or the absence at the C-terminus of an additional hydrophobic and negatively charged tetrapeptide by-passing the mu-addressing ability of the amino-terminal moiety. A study of 20 Tyr-D-X-Phe-Y-NH2 analogs with substitution of X and Y by neutral, hydrophobic, aromatic amino acids as well as by charged amino acid residues shows that tetrapeptides maintain high binding affinity and selectivity for the mu-opioid receptor. Although residue in position 4 serves a delta-address function, the tripeptide motif at the C-terminus of dermenkephalin and deltorphin I are critical components for high selectivity at delta-opioid receptor. Results demonstrate that mu- and delta-opioid receptors share topologically equivalent ligand-binding domains, or ligand-binding sequences similarities, that recognized Tyr-D-X-Phe as a consensus message-binding sequence. The delta-receptor additionally contains a unique address subsite at or near the conserved binding domain that accommodates the C-terminal tetrapeptide motif of dermenkephalin and deltorphin I.
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Affiliation(s)
- S Charpentier
- Laboratoire de Bioactivation des Peptides, Institut Jacques Monod, Université Paris 7, France
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247
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Seethaler G, Chaminade M, Vlasak R, Ericsson M, Griffiths G, Toffoletto O, Rossier J, Stunnenberg HG, Kreil G. Targeting of frog prodermorphin to the regulated secretory pathway by fusion to proenkephalin. J Cell Biol 1991; 114:1125-33. [PMID: 1894691 PMCID: PMC2289141 DOI: 10.1083/jcb.114.6.1125] [Citation(s) in RCA: 24] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
We have investigated the sorting and processing of the amphibian precursor prepro-dermorphin in mammalian cells. Dermorphin, a D-alanine-containing peptide with potent opioid activity, has been isolated from the skin of the frog Phyllomedusa sauvagei. The maturation of this peptide from the precursor involves several posttranslational steps. Recombinant vaccinia viruses were used to infect AtT-20, PC12, and HeLa cells to study the sorting and processing of prepro-dermorphin. While this precursor was not processed in any of the examined cell lines, AtT-20 cells were able to process approximately 40% of a chimeric precursor consisting of the first 241 amino acids of prepro-enkephalin fused to a carboxy-terminal part of pro-dermorphin. By immunogold-EM, we could show that the chimeric protein, but not pro-dermorphin, was sorted to dense-core secretion granules. The processing products could be released upon stimulation by 8-Br-cAMP. We conclude that the pro-enkephalin part of the fusion protein contains the information for targeting to the regulated pathway of secretion, while this sorting information is missing in pro-dermorphin. This indicates that sorting mechanisms may differ between amphibian and mammalian cells.
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Affiliation(s)
- G Seethaler
- Institute of Molecular Biology, Austrian Academy of Sciences, Salzburg
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248
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Ohta N, Kubota I, Takao T, Shimonishi Y, Yasuda-Kamatani Y, Minakata H, Nomoto K, Muneoka Y, Kobayashi M. Fulicin, a novel neuropeptide containing a D-amino acid residue isolated from the ganglia of Achatina fulica. Biochem Biophys Res Commun 1991; 178:486-93. [PMID: 1859408 DOI: 10.1016/0006-291x(91)90133-r] [Citation(s) in RCA: 90] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
A novel pentapeptide containing a D-amino acid residue was purified from the central ganglia of the African giant snail Achatina fulica Ferussac, and it was named fulicin. The primary structure of the peptide was determined to be Phe-D-Asn-Glu-Phe-Val-NH2. Fulicin potentiated tetanic contraction of the penis retractor muscle of this snail at very low concentrations, and also showed modulatory actions on the activity of the buccal and ventricular muscles and the central ganglionic neurons.
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Affiliation(s)
- N Ohta
- Physiological Laboratory, Faculty of Integrated Arts and Sciences, Hiroshima University, Japan
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249
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Fujimoto K, Kubota I, Yasuda-Kamatani Y, Minakata H, Nomoto K, Yoshida M, Harada A, Muneoka Y, Kobayashi M. Purification of achatin-I from the atria of the African giant snail, Achatina fulica, and its possible function. Biochem Biophys Res Commun 1991; 177:847-53. [PMID: 1675568 DOI: 10.1016/0006-291x(91)91867-c] [Citation(s) in RCA: 45] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Achatin-I previously purified from the ganglia of the African giant snail Achatina fulica was isolated from the atria of this snail. Achatin-I appeared to enhance the cardiac activity in two ways; centrally this peptide increased impulse frequency and produced spike broadening of the identified heart excitatory neuron, PON, and peripherally it enhanced amplitude and frequency of the heart beat. Achatin-I showed excitatory actions not only on the heart but on several other muscles.
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Affiliation(s)
- K Fujimoto
- Physiological Laboratory, Faculty of Integrated Arts and Sciences, Hiroshima University, Japan
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250
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Fisher GH, D'Aniello A, Vetere A, Padula L, Cusano GP, Man EH. Free D-aspartate and D-alanine in normal and Alzheimer brain. Brain Res Bull 1991; 26:983-5. [PMID: 1933416 DOI: 10.1016/0361-9230(91)90266-m] [Citation(s) in RCA: 150] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
In this report we present evidence for the presence of free D-aspartic acid (D-Asp) and D-alanine (D-Ala) in the white and gray matter of normal human brains and brains of individuals with Alzheimer's disease. D-Asp occurs at about the same concentration in the gray matter of both normal (18.6 nmol/g) and Alzheimer (14.8 nmol/g) brains, whereas in white matter its concentration is more than two times higher in normal than Alzheimer brains (22.4 and 10.5 nmol/g, respectively). D-Ala occurs in white matter at approximately the same concentration in both normal and Alzheimer brains (12.3 and 13.8 nmol/g, respectively), whereas in Alzheimer gray matter the D-Ala concentration is more than twice that found in normal gray matter (20.8 and 9.5 nmol/g, respectively). However, when the results are expressed as a percentage of D-amino acid/D+L, only small differences occur in all tissues examined.
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Affiliation(s)
- G H Fisher
- Department of Chemistry, Barry University, Miami Shores, FL 33161
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