1 The effects on tryptophan distribution and metabolism of drugs altering plasma unesterified fatty acid (UFA) concentration were investigated in the rat. 2 UFA and plasma free (i.e. ultrafilterable) tryptophan altered in the same direction. 3 Catecholamines and l‐DOPA increased both plasma UFA and free tryptophan. l‐DOPA also increased brain tryptophan and 5‐hydroxyindoleacetic acid (5‐HIAA) but decreased brain 5‐hydroxytryptamine (5‐HT). 4 Aminophylline increased plasma UFA and free tryptophan and also brain tryptophan, 5‐HT and 5‐HIAA. Food deprivation had qualitatively similar effects. 5 Insulin decreased plasma UFA and free tryptophan in both fed and food‐deprived rats. However, while in fed rats these changes were associated with small decreases of brain indoles, in food‐deprived animals small increases occurred. 6 Nicotinic acid had only small effects in fed rats but it opposed both the UFA and indole changes in food‐deprived animals. Total plasma tryptophan increased in nicotinic acid treated, food‐deprived rats. 7 There was a tendency towards inverse relations between changes of plasma free and total tryptophan. 8 The results suggest that drugs which influence plasma UFA through actions on cyclic AMP thereby alter the binding of tryptophan to plasma protein and that this leads to altered distribution and metabolism of tryptophan.
British Journal of Pharmacology – Wiley
Published: Feb 1, 1974
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera