A possible immunoregulatory function for [Met]-enkephalin-Arg6-Phe7 involving human and invertebrate granulocytes.
J Neuroimmunol
; 31(2): 97-103, 1991 Feb.
Article
em En
| MEDLINE
| ID: mdl-1991823
ABSTRACT
Opioid peptides and their analogs have been shown to stimulate adherence, conformational changes and locomotory activity in human as well as invertebrate granulocytes. The present study demonstrates that [Met]-enkephalin-Arg6-Phe7, an opioid substance thus far not included in these immunological tests, exhibits stimulatory effects comparable to those of [Met]-enkephalin in this regard. Furthermore, since neutral endopeptidase 24.11 (enkephalinase; CD10/NEP) exists in invertebrate immunocyte membranes, we demonstrate that its specific inhibitor, phosphoramidon, potentiates the effects of the heptapeptide in inducing conformational change in both human and invertebrate granulocytes. Additionally, the major metabolic products of NEP activity, Phe-Met-Arg-Phe and Tyr-Gly-Gly, appear to be potent antagonists of this enzyme activity, especially the tetrapeptide. The effects of heptapeptide stimulation showed a major difference between vertebrate and invertebrate immunocytes with respect to their time course, namely, the speed of their onset. [Met]-enkephalin-Arg6-Phe7 markedly stimulated the locomotory activity of these cells which becomes most noticeable within 15-45 min for Mytilus cells and in a 5-15 min period for human cells. It also enhanced the mobility and velocity of the responsive human (5 microns/min) and invertebrate cells (2.1 microns/min).
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Base de dados:
MEDLINE
Assunto principal:
Encefalina Metionina
/
Granulócitos
/
Sistema Imunitário
Limite:
Animals
/
Humans
Idioma:
En
Ano de publicação:
1991
Tipo de documento:
Article