Effect of dietary limiting amino acid in prepyriform cortex on food intake.
The mechanisms underlying the reduced intake of an amino acid-imbalanced diet (imbalanced diet) appears to involve a decrease in the content of the dietary limiting amino acid (DLAA) in the prepyriform cortex (PPC). Intake of imbalanced diet was increased from 45-50 to 70-75% of baseline after bilateral injection of the DLAA directly into the PPC, following an inverted U-shaped dose-response curve. Injections had no effect on intake of basal diets. Injection of the DLAA into the PPC reversed the aversion to imbalanced diet in choice studies, as rats selected an imbalanced diet over protein-free diet after such injections. Intake of imbalanced diet did not increase after a nonlimiting amino acid was injected into the PPC or after injections of the DLAA into other brain areas. Results were similar when either threonine or isoleucine was the DLAA. These results confirm that the decrease in the concentration of the DLAA in the PPC is involved in the reduction in intake of imbalanced diets.
Beverly
J L
JL
Department of Physiological Sciences, School of Veterinary Medicine, University of California, Davis 95616.
Gietzen
D W
DW
Rogers
Q R
QR
D000596:Amino Acids / Q000008:administration & dosage* / Q000494:pharmacology; D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology*; D004032:Diet; D004305:Dose-Response Relationship, Drug; D004435:Eating / Q000502:physiology*; D007267:Injections; D007532:Isoleucine / Q000008:administration & dosage; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013912:Threonine / Q000008:administration & dosage
D000596:Amino Acids; D007532:Isoleucine; D013912:Threonine