title: Possible modulatory role of non-activated lymphocytes on insulin secretion.
abstract: 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.
authors.affiliation: Departamento de Fisiologia e Biofísica, Universidade de São Paulo, Brasil.
authors.forename: A F
authors.initials: AF
authors.lastname: Meira
authors.forename: P M
authors.initials: PM
authors.lastname: Freire
authors.forename: M S
authors.initials: MS
authors.lastname: Rocha
authors.forename: R
authors.initials: R
authors.lastname: Curi
authors.forename: T M
authors.initials: TM
authors.lastname: Zorn
authors.forename: A R
authors.initials: AR
authors.lastname: Carpinelli
mesh_terms: D000818:Animals; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans; D008214:Lymphocytes / Q000378:metabolism*; D008297:Male; D051381:Rats
chemical_list: D007328:Insulin