Monoamine-containing basal cells in the taste buds of the newt Triturus pyrrhogaster.

Monoamine-containing cells were examined by fluorescence histochemistry and electron microscopy. Two or three serotonin-like fluorescent cells were located just above the basal lamina and failed to reach the free surface of the taste bud. Ultrastructurally this cell type was characterized by the presence of dense-cored vesicles and finger-like cytoplasmic processes. Many characteristics of Merkel cells were present.