Fig. 10. 5-HT_7Hel receptor immunoreactivity in identified Helisoma ciliary cells. Nomarski differential interference contrast (DIC) images (left panels) and corresponding fluorescence micrographs (right panels) of tissue explants containing identified ciliary cells that were processed for 5-HT_7Hel immunoreactivity. Arrows indicate the apical surface of the ciliary cells. (A) Immunopositive pedal ciliary cells. (B) Immunonegative pedal ciliary cells. (C) Immunopositive dorsolateral ciliary cells. (D) Immunonegative dorsolateral ciliary cells. (E) As with 5-HT_1Hel immunoreactivity, 5-HT_7Hel immunoreactivity was restricted to non-ciliary epithelial cells (asterisks) surrounding the scattered single ciliary cell. Scale bars, 10 µm.