Serotonin2c Receptor Constitutive Activity: In vivo Direct and Indirect Evidence and Functional Significance
Sylvia Navailles, Mélanie Lagière, Martin Guthrie and Philippe De Deurwaerdère
Pages 98-107 (10)
Serotonin2c (5-HT2C) receptors are widely expressed in the central nervous system where they play a pivotal
role in the regulation of neuronal network excitability. Along with this fundamental physiological function, 5-HT2c
receptors are thought to be implicated in the pathophysiology of several neuropsychiatric disorders and have become a
major pharmacological target for the development of improved treatments of these disorders. In the past decade, many
studies have focused on the constitutive activity of 5-HT2c receptors and the therapeutic potential of drugs acting as
inverse agonists. Although the constitutive activity of the 5-HT2c receptor has been clearly described in vitro, the
transposition of this concept to living animals is often difficult to ascertain. Nevertheless, cumulating evidence has
demonstrated the functional relevance of such property in regulating physiological systems in vivo both at the level of the
central and peripheral nervous systems. The present review provides an update of the growing number of studies that
show, by means of pharmacological tools, the participation of the constitutive activity of 5-HT2c receptors in the control
of various biochemical and behavioural functions in vivo and emphasizes the functional organization of this constitutive
control together with the phasic and tonic (involving the spontaneous release of 5-HT) modalities of the 5-HT2c receptor
in the brain.
Basal ganglia, c-Fos expression, constitutive activity, dopamine release, 5-HT2c receptor, motoneuron excitability,
orofacial activity, rabbit head bobs.
Institut des Maladies Neurodégénératives, UMR CNRS 5293, Université Bordeaux 2, 146 rue Léo Saignât, 33076 Bordeaux Cedex, France.