[There is only 1 type of A cells in the islands of Langerhans of the pancreas].
Differences of A cell reactions in Langerhans islets can be explained by variations of the activity of a same cell. Resting of this cell by injection of glucagone or glucose makes it argyrophilic and abolishes tryptophan reaction. Stimulation of A cells by fasting or injection of insulin suppresses argyrophilism and makes the tryptophane reaction positive. A1 and A2 cells cannot be opposed. Variations of glucagone production explains diversity of the reactions in A cells.
D006801:Humans; D007515:Islets of Langerhans / Q000166:cytology*
Il n'existe qu'un seul type de cellules A dans les ilots de Langerhans du pancreas