| REVIEW ARTICLE
|Year : 1993 | Volume
| Issue : 2 | Page : 60-67
5-Hydroxytryptamine receptor subtypes and antimigraine action
PR Saxena, WA Bax, MD Ferrari
The Nomenclature Committee of the Serotonin Club now recognizes four distinct types 5-hvdroxvtrvptamine (5-HT: serotonin) receptors called 5-HTI. 5-HT2. 5-HT3 and 5-HT4 . There is-now good evidence that the 5-HT1; and 5-HT2 receptors areheterogeneous and have several subtypes.Besides these receptors, there is another category of the so-called "orphan" receptors which await definitive classification. Two such kinds of receptors are collectively known as 5-HT1-like receptors; in order to distinguish between them they are sometimes denoted as 5-HT1X and 5-HT1Y, which mediate vasoconstriction (predominantly, but not exclusively, of cephalic vessels) and vasodilatation, respectively. Vasoconstriction in most other vessels is usually mediated by 5HT2A receptors. Injection of 5-HT and several other agonists at 5-HT1 -like receptors redistribute carotid blood flow so that arteriovenous anastomotic blood flow decreases despite, sometimes, an increase in tissue (arteriolar) blood Row. There is now good evidence that agonists at 'constrictor' 5HT1 -like (5-HT1x) receptors have the ability to abort migraine attacks. The other 5-HT receptors, including the 5-HT2A, 5-HT2c and 5-HT3 receptors, do not seem to play an important role in the antimigraine action of the currently available drugs.
P R Saxena
Source of Support: None, Conflict of Interest: None