WAY100635 blocks the hypophagia induced by 8-OH-DPAT in the hypothalamic nuclei.
This study examined the influence of pretreatment with N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-N-(2-pyridinyl) cyclohexane carboxamide maleate (WAY100635, full 5-HT1A receptor antagonist, 37 nmol) on feeding effects evoked by local injections of 8-hydroxy-2-(di-n-propylamino)-tetralin (8-OH-DPAT, 5-HT(1A) and 5-HT(7) receptor agonist, 6 nmol) into the LH and into the ARC of female rats adapted to a wet mash diet (enriched with 10% sucrose), during diestrus or estrus. The results showed that the LH-pretreatment with WAY100635 suppressed the hypophagic effects evoked by 8-OH-DPAT during estrus as well as diestrus. The ARC pretreatment with WAY100635 blockaded the hypophagia evoked by 8-OH-DPAT in estrus rats. The previous treatment with WAY100635 in the ARC also suppressed the feeding duration decrease evoked by 8-OH-DPAT in estrus. The latency to start feeding, the drinking behavior and the durations of other non-ingestive behaviors were not affected by the different treatments, hypothalamic regions (LH or ARC), and/or estrous cycle stages (diestrus and estrus), except for the locomotion duration increase after 8-OH-DAPT in LH-pretreated rats in diestrus. The present findings confirm our previous suggestion that ARC- and the LH-5-HT(1A) receptors participate in the serotonergic control of feeding and that these feeding-related serotonergic circuits in LH are affected by ovarian hormones, since the treatment with WAY100635 evoked a hypophagia response during the diestrus phases.
Department of Physiological Sciences-Centre of Biological Sciences Federal University of Santa Catarina (UFSC) Florianopolis, Brazil.
Sérgio Murilo
SM
Steffens
Danielle
D
Beckman
Moacir Serralvo
MS
Faria
José
J
Marino-Neto
Marta Aparecida
MA
Paschoalini
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000494:pharmacology*; D000704:Analysis of Variance; D000818:Animals; D004327:Drinking Behavior / Q000187:drug effects; D004347:Drug Interactions; D030762:Estrous Cycle / Q000187:drug effects; D005247:Feeding Behavior / Q000187:drug effects*; D005260:Female; D007026:Hypothalamic Area, Lateral / Q000187:drug effects; D010879:Piperazines / Q000494:pharmacology*; D011725:Pyridines / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D012702:Serotonin Antagonists / Q000494:pharmacology*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*; D013493:Suprachiasmatic Nucleus / Q000187:drug effects*
D010879:Piperazines; D011725:Pyridines; D012702:Serotonin Antagonists; D017366:Serotonin Receptor Agonists; C090413:N-(2-(4-(2-methoxyphenyl)-1-piperazinyl)ethyl)-N-(2-pyridinyl)cyclohexanecarboxamide; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin