5-HT receptor

5-hydroxytryptamine receptors or 5-HT receptors, or serotonin receptors are found in the central and peripheral nervous systems. Families Subtypes The 7 general serotonin receptor classes include a total of 14 known serotonin receptors. The 15th receptor 5-HT1P has been distinguished on the basis of functional and radioligand binding studies, its existence has never been definitely affirmed or refuted. The specific types have been characterized as follows: Note that there is no 5-HT1C receptor since, after the receptor was cloned and further characterized, it was found to have more in common with the 5-HT2 family of receptors and was redesignated as the 5-HT2C receptor. Very nonselective agonists of 5-HT receptor subtypes include ergotamine (an antimigraine), which activates 5-HT1A, 5-HT1D, 5-HT1B, D2 and norepinephrine receptors. LSD (a psychedelic) is a 5-HT1A, 5-HT2A, 5-HT2C, 5-HT5A and 5-HT6 agonist. ==Expression patterns==

The genes coding for serotonin receptors are expressed across the mammalian brain. Genes coding for different receptors types follow different developmental curves. Specifically, there is a developmental increase of HTR5A expression in several subregions of the human cortex, paralleled by a decreased expression of HTR1A from the embryonic period to the post-natal one. ==5-HT-like==

A number of receptors were classed as "5-HT-like" - by 1998 it was being argued that, since these receptors were "a heterogeneous population of 5-HT1B, 5-HT1D and 5-HT7" receptors the classification was redundant. == References ==