Infusion of the 5-hydroxytryptamine agonists RU24969 and TFMPP into the paraventricular nucleus of the hypothalamus causes hypophagia

✍ Scribed by P. H. Hutson; T. P. Donohoe; G. Curzon

• Book ID: 104651211
• Publisher: Springer
• Year: 1988
• Tongue: English
• Weight: 275 KB
• Volume: 95
• Category: Article
• ISSN: 0033-3158
• DOI: 10.1007/bf00172974

✦ Synopsis

The 5-HT1B agonist RU24969 when given either systemically (1 mg/kg SC) or by infusion (0.5, 1.0, 2.0 micrograms) into the region of the paraventricular nucleus of the hypothalamus caused dose-dependent hypophagia in rats previously deprived of food for 18 h. Similar results were obtained at the above dosages of 1-[3-(trifluoromethyl) phenyl] piperazine (TFMPP), which acts on 5-HT1B and possibly also on 5-HT1C receptors. Neither drug significantly affected locomotion following central administration. Food intake was significantly decreased when the 5-HT1A agonist 8-OH-DPAT was given systemically (1 mg/kg SC) to rats previously deprived of food but was unaffected when 8-OH-DPAT (1 microgram) was infused into the paraventricular nucleus of both food-deprived and free feeding rats. Therefore, hypophagia occurs when hypothalamic 5-HT1B (and possibly 5-HT1C) but not 5-HT1A receptors are activated.