Dissertation > Excellent graduate degree dissertation topics show

Analgesis, Addiction Studies and Molecular Modelling of Three Endomorphin Analogs

Author: ZhuBeiBei
Tutor: ChenQiang
School: Lanzhou University
Course: Biochemistry and Molecular Biology
Keywords: Endomorphin Analogs Analgesis Conditioned Place Preference Molecular Modeling
CLC: R96
Type: Master's thesis
Year: 2007
Downloads: 87
Quote: 0
Read: Download Dissertation

Abstract


Endomorphin-1(EM-1, Tyr-Pro-Trp-Phe-NH2) and endomorphin-2(EM-2, Tyr-Pro-Phe-Phe-NH2) are two endogenous opioid peptides with high affinity and selectivity for mu-opioid receptors (MOR) and have extensive pharmacological effects especially mediate high potent analgesis effects. Since theμ-opioid receptors mediate the most prominent pharmacological effects of morphine, endomorphins are important model peptides in the search toward new analgesics. But treatment of pain with opioids is limited by their potential abuse liability. In an effort to develop analgesics without this side effect, an unbiased conditioned place preference(CPP) paradigm was used to evaluate the reward effect of endomorphins and their analogs . In this paper, we focused on the anlagesis and CPP relationship studies of endomorphins and their analogs, and tried to give some possible explainations for the mechanism by the molecular modeling study.Pre- and post-conditioning free-movement were measured on day 1 and day 5, respectively. Conditioning sessions were conducted twice daily from day 2 through day 4 consisting of the alternate injection of conditioning drug or vehicle. Intracerebroventricular (i.c.v.) injection of endomorphin-1 (0.5-6 nmol/kg) induced place preference in a dose-dependent manner; whereas, [D-V4-Bzl]EM1(6.67nmol/kg, icv, 50% MPE) produced significant analgesic effects, however, it failed to show reward properties in the standard 45- min conditioned place preference (CPP) paradigm. But endomorphin-2 (1-5 nmol/kg) dose-dependently induced conditioned place aversion (CPA) . EM-2 analogs Tyr-Pro-(L-aminoxy Phe)-PheNH2 and Tyr-Pro-(D-aminoxy Phe)-PheNH2(5-20nmolkg-1), with N-0 turn structures at the Pro2-aminoxy-Phe3 position, had low antinociceptive efficacy and didn’t induce CPA.To further investigate the structure characteristics, which may have great influence on the binding procedure and activation mechanism, of our analogs, we’ve used the ligand docking and molecular dynamic simulation (MDS) methods to explore these features. By our computational studies, we found that the ligand with higher affinity tend to adopt the more extended conformation which may facilitate the interactions, like hydrogen-bond and aromatic contact, between the ligand and the receptor. And we also found some common movements concerning the trans-membrane (TM) region 3, 4, 5 and 6 of the receptor when bound with our ligands.

Related Dissertations

  1. Spectroscopy and molecular modeling studies Chloramphenicol - cyclodextrin,TQ461
  2. Using ReaxFF reactive molecular dynamics study acidic ZSM-5 type zeolite catalyzed methanol to olefins process,TQ203.2
  3. Antigen Design for Deoxynivalenol and the Direct Competitive Enzyme-linked Immunosorbent Assay,R392.1
  4. Preparation and Characteristics of Silica Surface Molecularly Imprinted Polymer for Gasoline Desulfurization,O631.3
  5. Rats Chronic Mophine-dependent Behaviors and Palmitoylation on PSD-95 in Hippocampus and Nucleus Accumbens,R749.6
  6. Molecular Simulation Study of Gas Mixtures Separation in Metal-Organic Frameworks,TQ028.15
  7. Molecular Simulation Study of Diffusion of N-Alkanes in MOF-5 Metal-Organic Framework,TQ013.1
  8. Study the Brain-targeting Nanoparticles of HDAPC, an Analog of EM-1,R96
  9. The Contribution of 5-hydroxytryptamine 2A Receptors to the Expression of Endogenous Opioid Peptides in Peripheral Tissue,R96
  10. The Study on the Inhibition of Morphine Reward Activity of Neuropeptide S,R741
  11. Recognition of Sheared G:A Mismatched DNA by Ruthenium Polypyridyl Complex,O621.13
  12. Study on Anti-corrosion Property of Modified Styrene-acrylic Latex Coating and Its Molecular Dynamics Simulation,TQ630.1
  13. The Acquisition of Alcohol-conditioned Place Preference in PTSD-like Rats and Its Relationship with the Dopamine D1 Receptor,R749.5
  14. Studies on the Synthesis and Antioxidant Activity of Novel Curcumin Analogues,R285
  15. The Inclusion Research of β-Cyclodextrin and Three Aromatic Guest Molecules,O621.1
  16. Hydrophobic Charge Induction Chromatography: Ligand Screening, Coupling and Its Thermodynamic Analysis,O629
  17. Parallel Computing in Molecular Simulation,O641
  18. Mechanism of Proteinuria Prevention by 1,25-(OH)2D3 Analogs in Diabetic Nephropathy Rats,R587.1
  19. Molecular Simulation on Catalytic Performance of Modified SAPO-34,TQ426
  20. The Analysis of the Microstructure and the Performance of the Copolymer Rubber and the Molecular Simulation,TQ330.1
  21. Study on the Effect of CREB in Morphine Psychological Addiction in Rat,R749.6

CLC: > Medicine, health > Pharmacy > Pharmacology
© 2012 www.DissertationTopic.Net  Mobile