title: The distribution and turnover of tryptamine in the brain and spinal cord.
abstract: Tryptamine levels have been determined in mouse brain regions and spinal cord and in rat spinal cord. They were; caudate nucleus 2.5 ng X g-1, hypothalamus less than 0.5 ng X g-1, hippocampus less than 0.7 ng X g-1, olfactory bulb less than 0.7 ng X g-1, olfactory tubercles less than 0.6 ng X g-1, brain stem less than 0.4 ng X g-1, cerebellum less than 1.0 ng X g-1, and the "rest" 0.9 ng X g-1. The mouse whole brain was found to have 0.5 ng X g-1, the mouse spinal cord 0.3 ng X g-1, and the rat spinal cord 0.3 ng X g-1. These concentrations increased rapidly to 22.8 ng X g-1, 14.2 ng X g-1, and 6.6 ng X g-1 respectively at 1 hr after 200 mg X kg-1 pargyline. The turnover rates and half lives of tryptamine in the mouse brain and spinal cord and rat spinal cord were estimated to be 0.14 nmol X g-1 X h-1 and 0.9 min; 0.054 nmol X g-1 X h-1 and 1.5 min and 0.04 nmol X g-1 X h-1 and 1.6 min respectively. The aromatic L-aminoacid decarboxylase inhibitors NSD 1034 and NSD 1055 reduced synthesis of tryptamine in controls and pargyline pretreated animals. Tryptophan increased the concentrations of mouse striatal tryptamine and 5-hydroxytryptamine and brain stem 5-hydroxyindole acetic acid. p-Chlorophenylalanine reduced formation of 5-hydroxytryptamine and 5-hydroxyindoleacetic acid but did not change that of tryptamine.
mesh_terms: D000818:Animals; D001142:Aromatic-L-Amino-Acid Decarboxylases / Q000378:metabolism; D001921:Brain / Q000378:metabolism*; D001923:Brain Chemistry; D008297:Male; D051379:Mice; D008995:Monoamine Oxidase / Q000502:physiology; D010293:Pargyline / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000032:analysis / Q000378:metabolism*; D014363:Tryptamines / Q000378:metabolism*; D014364:Tryptophan / Q000494:pharmacology
chemical_list: D014363:Tryptamines; C030820:tryptamine; D014364:Tryptophan; D010293:Pargyline; D008995:Monoamine Oxidase; D001142:Aromatic-L-Amino-Acid Decarboxylases