The effects of the selective serotonin reuptake-inhibitor fluvoxamine on body weight in Zucker rats are mediated by corticotropin-releasing hormone

Brain serotonin plays a crucial role in the regulation of food intake and b ody weight homeostasis. Previous data suggest an interaction with corticotr opin-releasing hormone (CRH). To further examine the interaction between th ese neurotransmitters, the selective serotonin reuptake-inhibitor (SSRI) fl uvoxamine was given intraperitoneally in fa/fa Zucker rats with and without the CRH-receptor-antagonist a-helical CRH administered intracerebroventric ulary (i.c.v.). The saline treated animals gained weight. Fluvoxamine led t o a significant weight loss while not affecting food intake. Furthermore, i nsulin levels in this animal model were reduced following fluvoxamine admin istration. These effects were antagonized by alpha -helical CRH and are thu s most likely mediated via CRH or CRH-like peptides.