[PMID]: | 9559882 |
[Au] Autor: | Schwanstecher C; Meyer M; Schwanstecher M; Panten U |
[Ad] Endereço: | Institute of Pharmacology and Toxicology, Technical University of Braunschweig, Germany. |
[Ti] Título: | Interaction of N-benzoyl-D-phenylalanine and related compounds with the sulphonylurea receptor of beta-cells. |
[So] Source: | Br J Pharmacol;123(6):1023-30, 1998 Mar. |
[Is] ISSN: | 0007-1188 |
[Cp] País de publicação: | England |
[La] Idioma: | eng |
[Ab] Resumo: | 1. The structure activity relationships for the insulin secretagogues N-benzoyl-D-phenylalanine (NBDP) and related compounds were examined at the sulphonylurea receptor level by use of cultured HIT-T15 and mouse pancreatic beta-cells. The affinities of these compounds for the sulphonylurea receptor were compared with their potencies for K(ATP)-channel inhibition. In addition, the effects of cytosolic nucleotides on K(ATP)-channel inhibition by NBDP were investigated. 2. NBDP displayed a dissociation constant for binding to the sulphonylurea receptor (K(D) value) of 11 microM and half-maximally effective concentrations of K(ATP)-channel inhibition (EC50 values) between 2 and 4 microM (in the absence of cytosolic nucleotides or presence of 0.1 mM GDP or 1 mM ADP). 3. In the absence of cytosolic nucleotides or presence of GDP (0.1 mM) maximally effective concentrations of NBDP (0.1-1 mM) reduced K(ATP)-channel activity to 47% and 44% of control, respectively. In the presence of ADP (1 mM), K(ATP)-channel activity was completely suppressed by 0.1 mM NBDP. 4. The L-isomer of N-benzoyl-phenylalanine displayed a 20 fold lower affinity and an 80 fold lower potency than the D-isomer. 5. Introduction of a p-nitro substituent in the D-phenylalanine moiety of NBDP did not decrease lipophilicity but lowered affinity and potency by more than 30 fold. 6. Introduction of a p-amino substituent in the D-phenylalanine moiety of NBDP (N-benzoyl-p-amino-D-phenylalanine, NBADP) reduced lipophilicity and lowered affinity and potency by about 10 fold. This loss of affinity and potency was compensated for by formation of the phenylpropionic acid derivative of NBADP. A similar difference in affinity was observed for the sulphonylurea carbutamide and its phenylpropionic acid derivative. 7. Replacing the benzene ring in the D-phenylalanine moiety of NBDP by a cyclohexyl ring increased lipophilicity, and the K(D) and EC50 values were slightly lower than for NBDP. Exchange of both benzene rings in NBDP by cyclohexyl rings further increased lipophilicity without altering affinity and potency. 8. This study shows that N-acylphenylalanines interact with the sulphonylurea receptor of pancreatic beta-cells in a stereospecific manner. Their potency depends on lipophilic but not aromatic properties of their benzene rings. As observed for sulphonylureas, interaction of N-acylphenylalanines with the sulphonylurea receptor does not induce complete inhibition of K(ATP)-channel activity in the absence of inhibitory cytosolic nucleotides. |
[Mh] Termos MeSH primário: |
Transportadores de Cassetes de Ligação de ATP Ilhotas Pancreáticas/metabolismo Fenilalanina/análogos & derivados Canais de Potássio Corretores do Fluxo de Internalização Canais de Potássio/metabolismo Receptores de Droga/metabolismo
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[Mh] Termos MeSH secundário: |
Trifosfato de Adenosina/metabolismo Animais Cálcio/metabolismo Carbutamida/análogos & derivados Carbutamida/farmacologia Linhagem Celular Transformada Cricetinae Cicloexanos/farmacologia Glibureto/metabolismo Guanosina Difosfato/metabolismo Ilhotas Pancreáticas/citologia Ilhotas Pancreáticas/efeitos dos fármacos Masculino Camundongos Fenilalanina/metabolismo Fenilalanina/farmacologia Canais de Potássio/efeitos dos fármacos Receptores Sulfonilureia Trítio
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[Pt] Tipo de publicação: | JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T |
[Nm] Nome de substância:
| 0 (Cyclohexanes); 0 (Kcnj1 protein, mouse); 0 (Potassium Channels); 0 (Potassium Channels, Inwardly Rectifying); 0 (Receptors, Drug); 0 (Sulfonylurea Receptors); 10028-17-8 (Tritium); 146-91-8 (Guanosine Diphosphate); 41X3PWK4O2 (nateglinide); 47E5O17Y3R (Phenylalanine); 8L70Q75FXE (Adenosine Triphosphate); 9S304JL9M7 (benzoylphenylalanine); E3K8P4869P (Carbutamide); SX6K58TVWC (Glyburide); SY7Q814VUP (Calcium) |
[Em] Mês de entrada: | 9805 |
[Cu] Atualização por classe: | 141120 |
[Lr] Data última revisão:
| 141120 |
[Sb] Subgrupo de revista: | IM |
[Da] Data de entrada para processamento: | 980429 |
[St] Status: | MEDLINE |
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