D. Abramowski et al., LOCALIZATION OF THE 5-HYDROXYTRYPTAMINE(2C) RECEPTOR PROTEIN IN HUMANAND RAT-BRAIN USING SPECIFIC ANTISERA, Neuropharmacology, 34(12), 1995, pp. 1635-1645
The mouse 5-HT2C receptor and its third and fourth (C-terminal) cytopl
asmic domain have been expressed as fusion proteins in bacteria. After
purification antisera were generated against the fusion proteins. Cha
racterization by immunoblotting using eukaryotic cells expressing the
5-HT2C and 5-HT2A receptors showed that high titer antibodies could be
obtained only against the third and fourth cytoplasmic domain but not
the entire receptor. Affinity purified antibodies were used to study
the location of 5-HT2C receptors in rat and human brain sections. This
distribution was compared with the location of 5-HT2C receptor bindin
g sites as determined by [H-3]mesulergine, a 5-HT2C receptor radioliga
nd. The antibodies recognized sites in the rat choroid plexus, hippoca
mpus, cerebral cortex, striatum and substantia nigra with a similar di
stribution as the 5-HT2C binding sites. One antiserum directed against
the 5-HT2C receptor C-terminus crossreacted with the human receptor p
rotein in immunoblots. In human brain sections it labelled sites inclu
ding cerebral cortex, substantia nigra and cerebellum. Our results dem
onstrate that the antibodies are suitable to identify 5-HT2C receptors
in rat and human brain. They visualize a protein distribution which c
orrelates well with the location of the 5-HT2C receptor binding sites
as would be expected if affinity states do not influence the binding p
attern.