Figure 7. Immunocytochemical localization of noradrenaline to the posterior taste receptor cells of the rat tongue.

A, sample sections of foliate papillae immunostained with an antibody directed against noradrenaline. Sectioned tissue was reacted using an avidin-biotin technique with diaminobenzidine as the chromophore. Note the presence of several darkly stained taste receptor cells within the taste buds. The photomicrograph at the far right is a negative control section with omission of the primary antibody. Scale bars are 20 μm. B, examples of sample taste buds containing taste receptor cells immunopositive for NA-like immunoreactivity from foliate papillae. Tissue sections were reacted using an immunofluorescence technique with a Cy3-conjugated secondary antibody. Many taste receptor cells displayed intense fluorescent labelling in their cytoplasm while their nuclei remained clear and were devoid of any positive signal. The photomicrograph at the far right is a negative control section with omission of the primary antibody. Scale bars are 20 μm.