Effects of cocaine- and amphetamine-regulated transcript peptide, leptin and orexins on hypothalamic serotonin release.
We have studied the effects of cocaine- and amphetamine-regulated transcript (CART) peptide-(55-102), leptin, orexin-A and orexin-B on basal and depolarization (K(+) 15 mM)-induced serotonin (5-hydroxytryptamine, 5-HT) release from rat hypothalamic neuronal endings (synaptosomes) in vitro. We have found that leptin and CART peptide-(55-102) have no effect on 5-HT release, while orexin-A and orexin-B inhibit depolarization-stimulated serotonin release. We can conclude that leptin and CART peptide-(55-102), which play a physiological role as feeding inhibitors, do not acutely affect 5-HT release from hypothalamic synaptosomes; on the other hand, feeding induced by orexin-A and orexin-B could be partially explained by decreased 5-HT release.
Orlando
G
G
Department of "Scienze del Farmaco", School of Pharmacy, G.D'Annunzio University, via dei Vestini, 66013, Chieti, Italy.
Brunetti
L
L
Di Nisio
C
C
Michelotto
B
B
Recinella
L
L
Ciabattoni
G
G
Vacca
M
M
D000818:Animals; D002352:Carrier Proteins / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D007031:Hypothalamus / Q000187:drug effects* / Q000378:metabolism; D047908:Intracellular Signaling Peptides and Proteins; D020738:Leptin / Q000494:pharmacology; D008297:Male; D009419:Nerve Tissue Proteins / Q000494:pharmacology; D009479:Neuropeptides / Q000494:pharmacology; D000068797:Orexins; D011188:Potassium / Q000494:pharmacology; D011506:Proteins / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012701:Serotonin / Q000378:metabolism*; D013997:Time Factors; D014316:Tritium; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein
D002352:Carrier Proteins; D047908:Intracellular Signaling Peptides and Proteins; D020738:Leptin; D009419:Nerve Tissue Proteins; D009479:Neuropeptides; D000068797:Orexins; D011506:Proteins; D000098882:Cocaine- and Amphetamine-Regulated Transcript Protein; D014316:Tritium; D012701:Serotonin; D011188:Potassium