Feeding suppression induced by a fecal anorexigenic substance (FS-T).
Intraperitoneal (IP) injection of a fecal anorexigenic substance (FS-T) induced significant suppression of feeding and this suppression recovered on the second day. At 2 hr after IP injection, at the time of maximum feeding suppression, plasma glucose, insulin and free fatty acid (FFA) levels did not change but amino acid level decreased. Intra-third cerebral ventricle (ICV) infusion of FS-T induced parallel but more potent feeding suppression. Analysis of meal patterns demonstrated that suppression of feeding after ICV treatment continued into the second day. FS-T was applied electrophoretically to glucose-sensitive and non glucose-sensitive neurons in the lateral hypothalamic area (LHA) and to glucoreceptor and non glucoreceptor neurons in the ventromedial hypothalamic nucleus (VMH). It significantly inhibited glucose-sensitive neurons but not non glucose-sensitive neurons, and excited both neuron types in the VMH. FS-T might thus work directly through the hypothalamic feeding control centers to suppress feeding. Even after pronase treatment of FS-T, a non-dialysable fraction of large molecular weight, consisting of protein and carbohydrate, maintained the original anorexigenic activity.
D000596:Amino Acids / Q000097:blood; D000818:Animals; D001067:Appetite Depressants / Q000032:analysis*; D001786:Blood Glucose / Q000032:analysis; D001931:Brain Mapping; D003864:Depression, Chemical; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005243:Feces / Q000032:analysis*; D005247:Feeding Behavior / Q000187:drug effects; D007026:Hypothalamic Area, Lateral / Q000187:drug effects*; D007328:Insulin / Q000097:blood; D008297:Male; D051381:Rats; D014697:Ventromedial Hypothalamic Nucleus / Q000187:drug effects*
D000596:Amino Acids; D001067:Appetite Depressants; D001786:Blood Glucose; D005230:Fatty Acids, Nonesterified; D007328:Insulin