Basal cells of the frog's taste organ: fluorescence histochemistry with the serotonin analogue 5,7-dihydroxytryptamine in supravital conditions

We utilized the fluorescent serotonin analogue 5,7-dihydroxytryptamine (5,7DHT) to visualize basal cells in the frog's taste organ in supravital conditions. In whole mounts of lingual mucosa, specifical and detailed morphological visualization of fluorescent basal cells was obtained in the peripheral and central region of the intact taste organ; similar results were obtained after mechanical dissociation. Preincubation with serotonin prevented any fluorescence in basal cells. Electron microscopy showed good preservation of the ultrastructural morphology of the taste disk after exposure to 5,7DHT. The advantages of the current method as compared with conventional ones are discussed. This simple, reliable procedure will be useful to further define the biology of neuroendocrine cells in taste as well as in other organs.