Localization of 5-HT6 receptors at the plasma membrane of neuronal cilia in the rat brain

5-HT6 receptor-like immunoreactivity has been previously found in associati on with both neuronal dendrites and cilia in the striatum, nucleus accumben s, olfactory tubercle and islands of Calleja of the rat brain. Using immuno gold pre-embedding immunocytochemical techniques to investigate the subcell ular localization of 5-HT6 receptor-like immunoreactivity in cilia, we show ed that immunogold particles were associated with their plasma membrane, an d not with microtubules. This membrane localization is consistent with a po ssible physiological role, which is still unknown, of these receptors. (C) 2000 Elsevier Science B.V. All rights reserved.