Stimulation of 5-HT2A receptors in the paraventricular hypothalamus attenuates neuropeptide Y-induced hyperphagia through activation of corticotropin releasing factor.
The effect of 5-HT1 and 5-HT2 receptor agonists administered into the paraventricular hypothalamus was studied on the hyperphagia caused by neuropeptide Y (NPY) injected into the same area. The 5-HT2A/2C receptor agonist DOI (10-20 nmol/0.5 microliter) significantly reduced NPY overeating while the 5-HT1A/1B receptor agonist RU 24969 (3.5-14 nmol/0.5 microliter) and the 5-HT1B/2C receptor agonist mCPP (5-20 nmol/0.5 microliter) had no such effect. The 5-HT2A receptor antagonist spiperone (5 microgram/0.5 microliter) and the corticotropin releasing factor antagonist alpha-helical-CRF9-41 (0.5-1 micrograms/0.5 microliter) completely antagonized the effect of 10 nmol DOI.
Grignaschi
G
G
Istituto di Ricerche Farmacologiche Mario Negri, Milan, Italy.
Sironi
F
F
Samanin
R
R
D000662:Amphetamines / Q000494:pharmacology; D000818:Animals; D003346:Corticotropin-Releasing Hormone / Q000502:physiology*; D005247:Feeding Behavior / Q000187:drug effects / Q000502:physiology; D006963:Hyperphagia; D007211:Indoles / Q000494:pharmacology; D008297:Male; D009478:Neuropeptide Y / Q000494:pharmacology*; D010286:Paraventricular Hypothalamic Nucleus; D010879:Piperazines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin / Q000187:drug effects / Q000502:physiology*; D017366:Serotonin Receptor Agonists / Q000494:pharmacology*; D013134:Spiperone / Q000494:pharmacology
D000662:Amphetamines; D007211:Indoles; D009478:Neuropeptide Y; D010879:Piperazines; D044402:Receptor, Serotonin, 5-HT2A; D011985:Receptors, Serotonin; D017366:Serotonin Receptor Agonists; C018406:1-(3-trifluoromethylphenyl)piperazine; C025145:5-methoxy 3-(1,2,3,6-tetrahydro-4-pyridinyl)1H indole; D013134:Spiperone; D003346:Corticotropin-Releasing Hormone; C015952:4-iodo-2,5-dimethoxyphenylisopropylamine