Disease relevance of Htr5a

• 5-HT3 receptors in outside-out patches of N1E-115 neuroblastoma cells: basic properties and effects of pentobarbital [1].
• These results suggest that 5-HT released from mast cells is partly involved in the development of capsaicin-induced mouse ear edema via 5-HT2 receptors in the ear skin [2].

High impact information on Htr5a

• Pharmacological studies suggested that release of arachidonic acid and inositol phosphates was mediated by a type 2 5-HT (5-HT2) receptor [3].
• 5-HT-stimulated release of arachidonic acid was also detected in cortical neurons, which contain high levels of 5-HT2 receptors, but not striatum, spinal cord, or cerebellar granule cells, which have very low levels or are devoid of 5-HT2 receptors [3].
• Amino acid sequence comparisons revealed that this receptor was a close relative of the previously identified 5-HT5 receptor but was distant from all other 5-HT receptor subtypes; we therefore named it 5-HT5B [4].
• A fast solution exchange system (Dilger and Brett, 1990; Biophysics Journal 57: 723-731) with an exchange rate < 1 msec was used to study 5-HT3 (5-HT; 5-hydroxytryptamine) receptor-mediated currents in superfused outside-out patches of N1E-115 mouse neuroblastoma cells [1].
• The results obtained in this model with pentobarbital are compatible with the suggestion that the inhibitory action of pentobarbital on 5-HT3 receptors is dependent on the agonist-activated (open) channel [1].

Chemical compound and disease context of Htr5a

• Capsaicin-induced ear edema was significantly inhibited by preadministration of 5-HT2 receptor antagonists such as ketanserin (2 mg/kg, i.v.) and LY 53857 (1 mg/kg, i.v.), but not 5-HT1-, 5-HT3- and 5-HT4-receptor antagonists [2].
• Intradermal injection of alpha-methyl 5-HT (5-HT2-receptor agonist) and 5-HT into ear skin produced edema formation more potently than 8-OH-DPAT (5-HT1A agonist) and 2-methyl 5-HT (5-HT3 agonist) [2].
• Furthermore, 5-HT2-receptor antagonists partly prevented ear edema in response to substance P (SP), a putative mediator or capsaicin-induced edema, and compound 48/80, a releaser of vasoactive amines form mast cells [2].

Associations of Htr5a with chemical compounds

• The Htr1f, Htr5a, Htr5b, and Htr7loci, encoding four serotonin receptors, mapped to Chr 16, 5, 1, and 19, respectively [5].

References