Possible modulatory role of non-activated lymphocytes on insulin secretion.

Autor: Meira AF; Departamento de Fisiologia e Biofísica, Universidade de São Paulo, Brasil., Freire PM, Rocha MS, Curi R, Zorn TM, Carpinelli AR
Jazyk: angličtina
Zdroj: Brazilian journal of medical and biological research = Revista brasileira de pesquisas medicas e biologicas [Braz J Med Biol Res] 1996 Dec; Vol. 29 (12), pp. 1709-13.
Abstrakt: In order to study the probable physiological role of non-activated lymphocytes on islet B-cells, we incubated and perfused rat pancreatic islets in the presence of low (2.8 mM) and high (16.7 mM) glucose concentrations after pre-exposure for 60 min to rat lymphocytes or to substances secreted by lymphocytes. Insulin secretion and 86Rb+, 45Ca2+ and [3H]-phosphoinositide metabolite fluxes were lower compared to controls when islets were pre-exposed to lymphocytes but were not different when islets were pre-exposed to substances secreted by lymphocytes. These alterations in isotope flux suggest that, when lymphocytes and islets are in contact, closure of potassium channels and a paradoxical effect of glucose load on insulin release occur in the presence of low glucose concentrations. The alterations observed are probably due to a swift and direct action of lymphocyte secretion perhaps induced by a direct of islet cells.
Databáze: MEDLINE