Transformation of Glicentin-containing L-Cells into Glucagon-containing Cells by Enzymatic Digestion

Exposure of sections of ileal mucosa to enzymatic digestion with trypsin and carboxypeptidase B reveals a population of immunofluorescent cells after incubation with a specific C-terminally directed antiglucagon serum. These cells, unreactive before enzyme treatment, were identified as L-cells by their immunoreactivity to antiglicentin serum and to cross-reacting (N-terminal) antiglucagon sera. The presence in the L-cells of antigenic sites characteristic of the glucagon-containing cells (A-cells) emphasizes the close relationships between these two cell types, and it further supports the hypothesis of glicentin as a glucagon precursor.