The effect of dietary tyrosine levels on food intake in zinc-deficient rats.
The study was designed to determine the effect of dietary tyrosine levels on food intake in the zinc-deficient rat. This was accomplished by using free L-amino acids as the source of nitrogen and manipulating the tyrosine concentrations in the diet. Results showed that low dietary tyrosine significantly increased food intake in the zinc-deficient rat and significantly decreased the concentration of tyrosine in serum and anterior hypothalamus (AH). Reduced tyrosine levels in the AH led to decreases in the concentrations of norepinephrine (NE) and dopamine (DA) in the AH. The results allow us to suggest that the mechanism that suppresses food intake in the zinc-deficient rat involves the catecholaminergic neurons of the hypothalamus.
D000284:Administration, Oral; D000596:Amino Acids / Q000097:blood; D000818:Animals; D002395:Catecholamines / Q000032:analysis; D005247:Feeding Behavior / Q000187:drug effects*; D007031:Hypothalamus / Q000032:analysis; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D014443:Tyrosine / Q000378:metabolism / Q000494:pharmacology*; D015032:Zinc / Q000172:deficiency*
D000596:Amino Acids; D002395:Catecholamines; D014443:Tyrosine; D015032:Zinc