HRH3

Histamine is a ubiquitous messenger molecule released from mast cells, enterochromaffin-like cells, and neurons. Its various actions are mediated by histamine receptors H1, H2, H3 and H4. This gene encodes one of the histamine receptors (H3) which belongs to the family 1 of G protein-coupled receptors. It is an integral membrane protein and can regulate neurotransmitter release. This receptor can also increase voltage-dependent calcium current in smooth muscles and innervates the blood vessels and the heart in cardiovascular system.

Full Name

histamine receptor H3

Function

The H3 subclass of histamine receptors could mediate the histamine signals in CNS and peripheral nervous system. Signals through the inhibition of adenylate cyclase and displays high constitutive activity (spontaneous activity in the absence of agonist). Agonist stimulation of isoform 3 neither modified adenylate cyclase activity nor induced intracellular calcium mobilization.

Biological Process

Adenylate cyclase-inhibiting G protein-coupled acetylcholine receptor signaling pathway Source: GO_Central
Chemical synaptic transmission Source: GO_Central
Cognition Source: GO_Central
G protein-coupled receptor signaling pathway, coupled to cyclic nucleotide second messenger Source: GO_Central
Negative regulation of glutamate secretion Source: GO_Central
Negative regulation of serotonin secretion Source: GO_Central
Neurotransmitter secretion Source: ProtInc
Regulation of norepinephrine secretion Source: GO_Central

Cellular Location

Cell membrane

Topology

Extracellular: 1-39
Helical: 40-60
Cytoplasmic: 61-70
Helical: 71-91
Extracellular: 92-108
Helical: 109-129
Cytoplasmic: 130-156
Helical: 157-177
Extracellular: 178-196
Helical: 197-217
Cytoplasmic: 218-359
Helical: 360-380
Extracellular: 381-395
Helical: 396-416
Cytoplasmic: 417-445