INTERCELLULAR CA2-SECRETION IN PIG ISLETS OF LANGERHANS( WAVES SUSTAIN COORDINATE INSULIN)

Insulin release was investigated in parallel with changes in cytosolic calcium concentration, [Ca2+](i), in pig islets stimulated by glucose . After two days in culture, glucose stimulation failed to induce insu lin release, and caused limited [Ca2+](i) changes in few cells. After ten days, insulin response was partially restored and [Ca2+](i) record ings revealed a slow oscillatory activity of the whole islet. Slow osc illations appeared to be due to the average [Ca2+](i) variations resul ting from the spreading of waves throughout the islet. These waves dem onstrate the reestablishment of functional cell coupling, which appear s to play a critical role in insulin release.