Effects and interactions between α-MSH and MCH/NEI upon striatal cAMP levels

• Published in: Peptides (New York, N.Y. : 1980) N.Y. : 1980), 1999-01, Vol.20 (5), p.611-614
• Main Authors: Sanchez, Mónica Silvina, Cremer, Marı́a Cecilia, Celis, Marı́a Ester
• Format: Article
• Language: English
• Subjects: alpha-MSH - pharmacology; Animals; Brain slices; Corpus Striatum - drug effects; Cyclic AMP; Cyclic AMP - analysis; Dose-Response Relationship, Drug; Drug Interactions; Hypothalamic Hormones - pharmacology; Male; MCH; Melanins - pharmacology; NEI; Nucleus Accumbens - drug effects; Oligopeptides - pharmacology; Pituitary Hormones - pharmacology; Putamen - drug effects; Rats; Rats, Wistar; Striatum; α-MSH
• ISSN: 0196-9781; 1873-5169
• DOI: 10.1016/S0196-9781(99)00014-5

It is known that α-MSH augments cAMP levels in rat brain slices containing accumbens and caudate-putamen nuclei. In this study we examined: a) the effect of other neuropeptides: MCH and NEI, on this cyclic nucleotide; b) if the effects of α-MSH on cAMP production can be modulated by addition of MCH or NEI to the incubation medium. Both MCH and NEI (3.6 μM) increased the production of cAMP, whereas at doses of 0.6 μM exerted no effects. When α-MSH 0.6 μM was added with NEI or MCH (0.6 μM), only MCH blocked the increase in the cAMP induced by α-MSH. Neither MCH nor NEI at the highest dose used (3.6 μM) had any additive effect on AMPc when added together with α-MSH. We conclude that, at a high concentration, (MCH/NEI)-like peptides can use the intracellular signal transduction linked to cyclic nucleotides in the CNS.