A method for concurrent measurement of picomole quantities of acetylcholine, choline, dopamine, norepinephrine, serotonin, 5-hydroxytryptophan, 5-hydroxyindoleacetic acid, tryptophan, tyrosine, glycine, aspartate, glutamate, alanine, and gamma-aminobutyric acid in single tissue samples from different areas of rat central nervous system
✍ Scribed by J.E. Smith; J.D. Lane; P.A. Shea; W.J. McBride; M.H. Aprison
- Publisher
- Elsevier Science
- Year
- 1975
- Tongue
- English
- Weight
- 969 KB
- Volume
- 64
- Category
- Article
- ISSN
- 0003-2697
No coin nor oath required. For personal study only.
✦ Synopsis
A rapid and sensitive method for sepalation and concurrent assay of 14 compounds at the picomole level in individual rat brain parts is described. The putative amino acid neurotransmitters (aspartate, y-aminobutyric acid, glutamate, and glycinel are extracted fi-om a 20-30 mg portion of the tissue with 5% TCA and assayed as their respective DNP-amino acid methyl ester derivatives by glc. Four other putative neurotransmitters (acetylcholine, dopamine, norepinephrine, and serotonin) and some of their precursors and metabolites (choline, tryptophan, 5hydroxytryptophan, 5-hydroxyindoleacetic acid, and tyrosine) are extracted in I N formic acid-acetone (v/v: 15/85) from the remaining tissue. The lipids are removed with a heptane-chloroform (v/v: 8/1) wash and the aqueous phase is dried at 37°C under Nz. The dried extract is dissolved in water (pH 4). With one portion of this solution, acetylcholine and choline are assayed using a radioenzymatic method whereas with the rest, dopamine, norepinephrine, serotonin, 5hydroxyindoleacetic acid, 5-hydroxytryptophan, tryptophan, and tyrosine are separated with three ion exchange resins arranged in tandem. These compounds are assayed fluorometrically with modified microadaptations of previously reported methods.