Melatonin receptors functions

Masana, M. I., Soares, J. M. Jr Dubocovich, M. L. (2005). 17beta-Estradiol modulates hMT(l) melatonin receptor function. Neuroendocrinology 81, 87-95. 

Brydon, L., Petit, L., Delagrange, P., Strosberg, A. D. Jockers, R. (2001). Functional expression of mt2 (mellb) melatonin receptors in human paz6 adipocytes. Endocrinology 142, 4264-71. 

Dubocovich, M. L., Rivera-Bermudez, M. A., Gerdin, M. J. and Masana, M. I. Molecular pharmacology, regulation and function of mammalian melatonin receptors. Front. Biol. 8 dl093—1108, 2003. 

SAR studies on melatonin analogues showed that methoxy and amido moieties are important for binding to melatonin receptors various substituents on the 2nd position of the indole ring enhance the binding affinity [52-54]. The conformational flexibility of the C-3 ethylamido side chain is probably responsible for the broad spectrum of biological activities. As a powerful antioxidant melatonin was shown to have significantly broader actions including oncostatic effects [55], immune system stimulation [56], and antiinflammatory functions [57,58]. 

Zahn PK, Lansmann T, Berger E, Speckmann EJ, Musshoff U (2003) Gene expression and functional characterisation of melatonin receptors in the spinal cord of the rat implications for pain modulation. J Pineal Res 35 24-31... 

Dubocovich ML, Masana Ml, Benloucif S. Molecular Pharmacology and function of melatonin receptor subtypes. In Olcese J, ed. Melatonin After Four Decades. New York Kluwer Academic, 2000 181-190. 

Melatonin and its receptors biological function in circadian sleep-wake regulation... 

Figure 10.3 Possible cellular pathways involved in the physiological modulation of GABAergic function by melatonin via the MTi receptor. See text for explanation. (See also Plate 2.)...

Functional receptors for melatonin have been localised and characterised on the pars tuberalis of a number of mammalian species (Morgan etal. 1991, Bockers et al. 1995, Bockmann et al. 1996). Using forskolin (1 [aM), as a non-specific stimulant of adenylate cyclase, melatonin (10 nM) was shown to inhibit the formation of cyclic AMP by 80-90 % in ovine pars tuberalis cells both before and after PercoU centrifugation (Morgan et al. 1991). 

Slominski RM, Reiter RJ, Schlabritz-Loutsevitch N, Ostrom RS, Slominski AT. Melatonin membrane receptors in peripheral tissues distribution and functions. Mol Cell Endocrinol 2012 351(2) 152-66. 

Functional end products of the essential amino acid tryptophan arise mainly through two distinctive pathways. The major pathway is degradation of tryptophan by oxidation, which fuels the kynurenine pathway (See 02011). The second and quantitatively minor pathway is hydroxylation of tryptophan and its subsequent decarboxylation to the indoleamine 5-hydroxytryptamine (serotonin) and subsequently melatonin. The metabolites of the kynurenine pathway, indicated as kynurenines, include quinolic acid and kynurenic acid. Quinolinic acid is an agonist of the NMDA receptor (see also section on glutamic acid), while kynurenic acid is a nonselective NMDA-receptor antagonist with a high affinity for the glycine site of the NMDA receptor (see also section on... 

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