"In vitro" postnatal expression of 5-HT7 receptors in the rat hypothalamus: an immunohistochemical analysis.

The neurotransmitter serotonin (5-HT) is involved in various physiological functions via multiple receptor subtypes. These have been classified in seven receptor families (5-HT1-7) on the basis of their structures and functional characteristics. In this study, we examined the expression of 5-HT7 receptors in the rat hypothalamic neurons cultured "in vitro" during postnatal development.

Serotonergic collateralized projections from Barrington's nucleus to the medial preoptic area and lumbo-sacral spinal cord.

In this study, we employed triple fluorescent labelling to reveal the distribution of the direct serotonergic neurons within Barrington's nucleus (BN) that supply branching collateral input to the medial preoptic area (MPA) and to the lumbo-sacral spinal cord (LSC). Immunocytochemical detection of the monoclonal antibody raised against serotonin was used for identification of the neurons. The projections were defined by injections of two retrograde tracers: fluoro gold and rhodamine in the MPA and LSC, respectively.