Dynorphin A analogs containing a conformationally constrained phenylalanine derivative in position 4: reversal of preferred stereochemistry for opioid receptor affinity and discrimination of kappa vs. delta receptors.
Chirality
; 13(3): 125-9, 2001.
Article
em En
| MEDLINE
| ID: mdl-11270320
ABSTRACT
Analogs of the opioid peptide [D-Ala8]dynorphin A-(1-11)NH2 containing optically pure (R)- and (S)-2-aminotetralin-2-carboxylic acid (Atc) in position 4 were synthesized and evaluated for opioid receptor affinity. These peptides are the first reported dynorphin A analogs containing a conformationally constrained amino acid in place of the important aromatic residue Phe4. By incorporating resolved Atc isomers, the opioid receptor affinity and the stereochemistry of the constrained residue could be unambiguously correlated. Both Dyn A analogs containing Atc in position 4 retained nanomolar affinity for kappa and mu opioid receptors. Unexpectedly the peptide containing (R)-Atc, corresponding to a conformationally constrained D-Phe analog, displaying higher affinity for both kappa and mu receptors than the peptide containing (S)-Atc. In contrast [D-Phe4,D-Ala8]Dyn A-(1-11)NH2 exhibited significantly lower affinity for kappa and mu receptors than the parent peptide, as expected. Conformational restriction of the Phe4 sidechain or incorporation of D-Phe in position 4 had the largest effect on delta receptor affinity, yielding compounds with negligible affinity for these receptors. Thus, there appear to be distinctly different structural requirements for this residue for kappa vs. delta receptors, and it is possible to completely distinguish between these two receptors by changing a single residue in Dyn A.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Fenilalanina
/
Dinorfinas
/
Receptores Opioides delta
/
Receptores Opioides kappa
/
Aminoácidos
/
2-Naftilamina
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Revista:
Chirality
Assunto da revista:
BIOLOGIA MOLECULAR
/
QUIMICA
Ano de publicação:
2001
Tipo de documento:
Article
País de afiliação:
Estados Unidos
País de publicação:
EEUU
/
ESTADOS UNIDOS
/
ESTADOS UNIDOS DA AMERICA
/
EUA
/
UNITED STATES
/
UNITED STATES OF AMERICA
/
US
/
USA