Disease relevance of Htr7

• Wild-type and mutant 5-HT7 receptors were expressed in insect cells using the baculovirus vectors [1].
• Recently, we have demonstrated that potassium channels containing G-protein-activated potassium channel 2 (GIRK2) subunits play a significant role in hypothermia induced by several neurotransmitter receptor agonists, including the serotonin (5-HT)1A/5-HT7 receptor agonist 8-OH-DPAT [R-(+)-8-hydroxy-2-(di-n-propylamino) tetralin] [2].
• Mouse skin and hamster melanomas also expressed 5HT2B and 5HT7 [3].

Psychiatry related information on Htr7

• Effects of a 5-HT7 receptor antagonist DR4004 on the exploratory behavior in a novel environment and on brain monoamine dynamics in mice [4].

High impact information on Htr7

• The 5-HT7 receptor was among a group of 5-HT receptors that were discovered using targeted cloning strategies 12 years ago [5].
• Important functional roles for the 5-HT7 receptor in thermoregulation, circadian rhythm, learning and memory, hippocampal signaling and sleep have also been established [5].
• The distributions of 5-HT7 receptor mRNA, immunolabeling and radioligand binding exhibit strong similarities, with the highest receptor densities present in the thalamus and hypothalamus and significant densities present in the hippocampus and cortex [5].
• Our results show that 5-HT may be a local regulator in mouse cumulus-oocyte complexes through its actions on cAMP and Ca2+ signaling, as mediated by 5-HT2A, 5-HT2B, and 5-HT7 receptors [6].
• This cAMP increase in cumulus cells could be mimicked by 5-HT agonists with the following order of potency: 5-HT > 8-hydroxy-2-(di-n-propylamino) tetralin = alpha-methyl-5-HT = 5-carboxamidotryptamine maleate > 2-[1-(4-piperonyl)piperazinyl]benzo-triazole, thereby supporting a preferential involvement of 5-HT7 receptors [6].

Biological context of Htr7

• Extracellular recordings from hypothalamic slices showed that circadian rhythm phase shifts to 8-OH-DPAT are attenuated in the 5-HT7 receptor KO mice also indicating a role for the receptor in the regulation of circadian rhythms [7].
• However, in the Porsolt swim test, 5-HT7 receptor knockout mice showed a significant decrease in immobility compared to controls, a phenotype similar to antidepressant treated mice [7].
• Reverse transcription and polymerase chain reaction technique (RT-PCR) was used in order to identify 5-HT1A and 5-HT7 receptor mRNA in immortalized LHRH cell lines [8].

Anatomical context of Htr7

• In mouse hippocampal neurons, activation of the endogenous 5-HT7 receptors significantly increased neurite length, whereas stimulation of 5-HT4 receptors led to a decrease in the length and number of neurites [9].
• Serotonergic modulation of retinal input to the mouse suprachiasmatic nucleus mediated by 5-HT1B and 5-HT7 receptors [10].

Associations of Htr7 with chemical compounds

• No hypothermic response to serotonin in 5-HT7 receptor knockout mice [11].
• These data suggest that oleamide may act at 5-HT7 receptors to elicit alterations in transcription that result in some of its physiological effects [12].
• Circadian rhythm phenotype of 5-HT7 receptor knockout mice: 5-HT and 8-OH-DPAT-induced phase advances of SCN neuronal firing [13].
• Serotonin directly stimulates luteinizing hormone-releasing hormone release from GT1 cells via 5-HT7 receptors [8].

Other interactions of Htr7

• There are similarities between the pharmacology of the 5-HT7 receptor and that of the 5-HT1A receptor, however the correlation between the in vivo potency in DBA/2J mice and 5-HT1A affinity was not significant [14].
• In the present study, we identified G12 as an additional G-protein that can be activated by another member of serotonin receptors, the 5-HT7 receptor [9].
• The present study examined whether serotonin (5-hydroxytryptamine; 5-HT)7 receptors play a role in the modulation of emotionality in mice using the selective 5-HT7 receptor antagonist 2a-[4-(4-phenyl-1,2,3,6-tetrahydropyridyl)butyl]-2a,3,4,5-tetrahydrobenzo (c,d)indol-2-(1H)-one (DR4004) [4].

References