title: Fluoxetine prevents 8-OH-DPAT-induced hyperphagia in Fischer inbred rats.
abstract: Ovariectomized, Fischer rats were hormonally primed with 10 μg estradiol benzoate and 50 μg progesterone or were treated with the sesame seed oil vehicle. Food intake was measured 2 h and 24 h after treatment with 0.25 mg/kg of the 5-HT(1A) receptor agonist, (±)-8-hydroxy 2-(di-n-propylamino) tetralin (8-OH-DPAT), 5 mg/kg of the selective serotonin reuptake inhibitor, fluoxetine, or their combination. Consistent with prior studies, two hour food intake of rats given fluoxetine and 8-OH-DPAT did not differ from vehicle controls. 8-OH-DPAT-induced hyperphagia, evident at 2 h, was blocked by co-treatment with fluoxetine. However, in contrast to prior studies, 5 mg/kg fluoxetine, alone, had only modest effects on food intake. Differences in our experimental protocols and/or the strain of rat may account for the lower anorectic response to fluoxetine. Nevertheless, the absence of a significant response to fluoxetine, alone, coupled with the drug's attenuation of the hyperphagic effect of 8-OH-DPAT, leads to the suggestion that the behavioral response to the combined treatment is more complex than that of simple additivity. Consistent with this suggestion, 24 h food intake of rats given 8-OH-DPAT and fluoxetine was lower than that of vehicle or 8-OH-DPAT-treated rats.
authors.affiliation: Department of Biology, Texas Woman's University, Denton, TX 76204, USA. cmiryala@twu.edu
authors.forename: Chandra Suma Johnson
authors.initials: CS
authors.lastname: Miryala
authors.forename: Navin
authors.initials: N
authors.lastname: Maswood
authors.forename: Lynda
authors.initials: L
authors.lastname: Uphouse
mesh_terms: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin / Q000037:antagonists & inhibitors* / Q000633:toxicity*; D000818:Animals; D000855:Anorexia / Q000139:chemically induced / Q000503:physiopathology; D004435:Eating / Q000187:drug effects / Q000502:physiology; D004958:Estradiol / Q000008:administration & dosage / Q000031:analogs & derivatives; D005260:Female; D005473:Fluoxetine / Q000494:pharmacology*; D006963:Hyperphagia / Q000139:chemically induced* / Q000503:physiopathology / Q000517:prevention & control*; D010052:Ovariectomy; D011374:Progesterone / Q000008:administration & dosage; D051381:Rats; D011916:Rats, Inbred F344; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology
chemical_list: D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D004958:Estradiol; D005473:Fluoxetine; D011374:Progesterone; D017367:Selective Serotonin Reuptake Inhibitors; C074283:estradiol 3-benzoate