Decrease in rat cerebral quinolinic acid concentration following chronic hydrocortisone treatment.
The effects of acute or repeated hydrocortisone administration were studied on the content of quinolinic acid (QUIN), 5-hydroxytryptamine (5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) assessed by mass fragmentography (QUIN) and high-performance liquid chromatography (5-HT and 5-HIAA) in various brain areas of the rat. Acute administration of the steroid did not significantly modify the brain content of these tryptophan metabolites while, when repeatedly administered at doses of 5 or 50 mg/kg i.p., hydrocortisone significantly reduced the cortical content of QUIN (by 28%, P less than 0.05 and 21%, P less than 0.05 respectively) and the utilization of 5-HT (as evaluated from the ratio 5-HIAA/5-HT by 22%, P less than 0.05 at 50 mg/kg). These data confirm that hydrocortisone administration affects tryptophan metabolism in the rat.
Connick
J
J
Department of Pharmacology, University of Florence, Italy.
Lombardi
G
G
Beni
M
M
Moroni
F
F
D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006854:Hydrocortisone / Q000494:pharmacology*; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D008297:Male; D011725:Pyridines / Q000378:metabolism*; D017378:Quinolinic Acid; D011805:Quinolinic Acids / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000378:metabolism
D011725:Pyridines; D011805:Quinolinic Acids; D012701:Serotonin; D006897:Hydroxyindoleacetic Acid; D017378:Quinolinic Acid; D006854:Hydrocortisone