5-HTib receptor modulation

Sarhan H, Cloez-Tayarani I, Massot O, Fillion MP, Fillion G (1999) 5-HTib receptors modulate release of [3H] dopamine from rat striatal synaptosomes. Naunyn Schmiedeberg s Arch Pharmacol 359 40-7... 

Glycine is the major inhibitory neurotransmitter in the spinal cord and brain stem. 5-HT presynaptically inhibits glycinergic synaptic transmission to rat brain stem hypoglossal motoneurons through 5-HTiB receptors (Umemiya and Berger 1995). The inhibition did not involve Ca2+ channel modulation. 

Mooney RD, Shi MY, Rhoades RW (1994) Modulation of retinotectal transmission by presynaptic 5-HTib receptors in the superior colliculus of the adult hamster. J Neurophysiol 72 3-13 Moreno-Delgado D, Torrent A, Gomez-Ramirez J, de Esch I, Blanco I, Ortiz J (2006) Constitutive activity of H3 autoreceptors modulates histamine synthesis in rat brain through the cAMP/PKA pathway. Neuropharmacology 51 517-23... 

An interesting development in this area is the possibility that there could be an endogenous ligand, for these receptors 5-HT-moduline. This is a tetrapeptide that is released from neurons and is claimed to be the first allosteric modulator of a G protein-coupled receptor to be identified so far. Functionally, 5-HT-moduline behaves like a 5-HTib antagonist and so increases terminal release of 5-HT (Massot et al. 1998) and it is thought that this could be an important step in maintaining a sustained increase in release of 5-HT during stress. 

Several different types of serotonin receptor (for example, S-HTi / 5-HT2A/ 5-HT2C/ 5-HTib/id) have been associated with the motor side effects of the SSRIs which may arise should these drugs be administered in conjunction with a monoamine oxidase inhibitor. The 5-HT3 receptor is an example of a non-selective cation charmel receptor which is permeable to both sodium and potassium ions and, because both calcium and magnesium ions can modulate its activity, the 5-HT3 receptor resembles the glutamate-NMDA receptor. Antagonists of the 5-HT3 receptor, such as ondansetron, are effective antiemetics and are particularly useful when... 

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