SATIETIN - FOS MAPPING OF PUTATIVE BRAIN SITES OF ACTION

A purified extract of a blood-borne satiety factor, called satietin, w as injected into the cerebral ventricles of rats that were either fed ad libitum or were food deprived. The animals were killed 2 h after in jection and their brains subsequently sectioned and stained for Fos-li ke immunoreactivity (Fos-IR) to determine the putative sites of action for satietin in the brain. Fos-IR was induced in only a few locations , the most prominent sites being the bed nucleus of the stria terminal is, the central nucleus of the amygdala, and the parvocellular divisio n of the paraventricular nucleus of the hypothalamus. Each of these ar eas has previously been implicated in the control of feeding behavior. Sires in the hindbrain that are associated with nausea were devoid of satietin-induced Fos-IR. Finally, these sites of action of satietin s how some differences from sites that are prominently activated by othe r classes of anorectic agents.