Amino acids and serotonin in Limax maximum after a tryptophan devoid diet.
1. Animals avoid diets lacking an essential amino acid, such as tryptophan (TRP), the precursor for serotonin (5-HT). 5-HT is important in the control of feeding. 2. To study the effects of TRP deprivation, slugs were fed TRP-devoid (DEV) or control (COR) diets. 3. Food intake was depressed in DEV, as expected, but after 2 weeks, the serontonergic metacerebral giant cell in DEV was still functional. 4. Neither brain 5-HT nor plasma TRP concentration was affected. 5. Compared with food-restricted animals that had reductions in most amino acids, the DEV group sustained a marked plasma amino acid imbalance.
Department of Physiological Sciences, School of Veterinary Medicine, University of California, Davis 95616.
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Gietzen
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Harris
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Carlson
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Gelperin
D000596:Amino Acids / Q000097:blood / Q000378:metabolism*; D000818:Animals; D001835:Body Weight; D001921:Brain / Q000378:metabolism; D004032:Diet; D004435:Eating; D012701:Serotonin / Q000097:blood / Q000378:metabolism*; D012908:Snails; D014364:Tryptophan / Q000008:administration & dosage / Q000378:metabolism*
D000596:Amino Acids; D012701:Serotonin; D014364:Tryptophan