Immunocytochemical Localization of Serotonin-Like Immunoreactivities in the Ciliated Epithelium of the Frog Palatine Mucosa

Abstract

Immunocytochemical localization of serotonin (5-HT)-like immunoreactivities was studies in the ciliated epithelium of the frog palatine mucosa by the peroxidase anti-peroxidase (PAP) method. 5-HT-like immunoreactivity was found only in the small granular vesicles (100–150 nm in diameter) and not in any mature large secretory granules or in other cell organellae in the goblet cells. No 5-HT-like immunoreactivities were found in any other epithelial and secretory cells in the palatine epithelium. It appears therefore that 5-HT-like immunoreactive granular vesicles have certain physiological effects on the ciliary movement of the ciliated cells or in the goblet cells.

Extensive presence of serotonergic cells and fibers in the peripheral nervous system of lampreys

“…The present results show that there is a close relation between these cells and the FSCs of the pharyngeal groves and gill seam. Studies carried out in echinoderms (Wada et al,1997), gastropods (Diefenbach et al,1991; McKenzie et al,1998; Uhler et al,2000; Doran et al,2004; Braubach et al,2006), mollusks (Pavlova et al,1999; Kuang and Goldberg,2001; Koss et al,2003), and amphibians (Maruyama et al,1984a,b; Naruse et al,2005) showed that 5‐HT plays a key role in the control of mucus secretion and ciliary beat frequency. The close relation between 5‐HT‐ir FSCs and the ciliated and mucous epithelia observed in lamprey may indicate that these cells are also involved in the control of the ciliary beat and mucus secretion.…”