TABLE 1

Brain expression and signaling of H3R isoforms from different species

The human H3R329a and H3R329b isoforms possess the same number of amino acids but differ in the region where alternative splicing occurs.

SpeciesIsoform (aa)Expression in the Central Nervous SystemSignalingReferences
HumanH3(445)Thalamus, striatum, cerebral cortex, cerebellum, amygdala, substantia nigra, hippocampus, hypothalamus, corpus callosum, spinal cord↓ cAMP, ↑ [Ca2+]iLovenberg et al., 1999; Nakamura et al., 2000; Cogé et al., 2001; Tardivel-Lacombe et al., 2001; Tsui, 2001; Wiedemann et al., 2002; Wellendorph et al., 2002; Gallagher and Yates, 2007; Bongers et al., 2007a,b
↑ p42/p44-MAPK,
↑ [35S]-GTPγS binding
H3(431)Amygdala, cerebellum, striatum, thalamus, prefrontal cortex, striatum,ND
H3(415)Thalamus, cerebellum, amygdala↑ [Ca2+]i
H3(365)Cerebellum, thalamus, hypothalamus, striatum, substantia nigra, hippocampus, amygdala, prefrontal cortex↑ [Ca2+]i, ↓ cAMP,
↑ [35S]-GTPγS binding
H3(329a)Substantia nigra, amygdala, cerebral cortex, hypothalamusNF
H3(326)Substantia nigra, prefrontal cortex, amygdala, hypothalamusND
H3(413)Striatum, amygdalaND
H3(453)ND↓ cAMP
H3(301)NDNF
H3(373)Hippocampus, substantia nigra, amygdala, hypothalamus↓ cAMP
H3(309)NDNF
H3(221)NDND
H3(409)NDND
H3(329b)NDND
H3(395)NDND
H3(379)NDND
H3(293)NDND
H3(290)NDND
H3(351)NDND
H3(340)NDND
MonkeyH3(445)Frontal cortex, parietal cortex, occipital cortex, parahippocampal gyrus, hippocampus, caudate nucleus, putamen, amygdala, thalamus, cerebellum↑ [Ca2+]iYao et al., 2003; Strakhova et al., 2008
H3(413)Frontal cortex, parietal cortex, para-hippocampal gyrus, caudate nucleus, putamen, amygdala, thalamus↑ [Ca2+]i
H3(410)Frontal cortex, parietal cortex, parahippocampal gyrus, caudate nucleus, putamen, amygdala, thalamus↑ [Ca2+]i
H3(335)Frontal cortex, parietal cortex, occipital cortex, parahippocampal gyrus, Hippocampus, caudate nucleus, putamen, amygdala, thalamus, cerebellumNF
RatH3(445)Cerebral cortex, hippocampus, midbrain, hypothalamus, striatum, brainstem, cerebellum, olfactory tuberculum, spinal cord↓ cAMP,Lovenberg et al., 2000; Drutel et al., 2001; Morisset et al., 2001; Bakker et al., 2006; Gbahou et al., 2012
↑ p42/p44-MAPK
H3(413)Cerebral cortex, hippocampus, midbrain, striatum↓ cAMP,
↑ p42/p44-MAPK
↑ [3H]AA release
↑ [35S]-GTPγS binding
H3(410)Cerebral cortex, hippocampus, midbrain, striatumND
H3(397)Cerebral cortex, hippocampus, midbrain, hypothalamus, striatum, olfactory tuberculum↓ cAMP,
↑ p42/p44-MAPK
H3(497)Cortex layers II–VIb, caudate-putamen, piriform cortex, hippocampusNF
H3(465)Cortex layers II–VIb, caudate-putamen, piriform cortex, hippocampusNF
H3(449)Cortex layers II–VIb, caudate-putamen, piriform cortex, hippocampusNF
MouseH3(445)Cerebral cortex, striatum, hypothalamus↑ [Ca2+]iChen et al., 2003; Rouleau et al., 2002
H3(413)Cerebral cortex, striatum, hypothalamusND
H3(397)Cerebral cortex, striatum, hypothalamusND
Guinea pigH3(445)Cerebral cortex, striatumNDTardivel-Lacombe et al., 2000
H3(415)Cerebral cortex, striatumND
DogH3(ND)NDNDIreland-Denny et al., 2001
  • ↑, increase; ↓, decrease; AA, arachidonic acid; [Ca2+]i, intracellular Ca2+ concentration; ND, not determined; NF, nonfunctional.