gamma-Aminobutyric acid, catecholamine and indoleamine determinations from the same brain region by high-performance liquid chromatography with electrochemical detection.
A new procedure for the measurement of gamma-aminobutyric acid, norepinephrine, dopamine, serotonin and 5-hydroxyindoleacetic acid from the same brain region was developed. In general, two separate high-performance liquid chromatographic runs were performed, one for the gamma-aminobutyric acid determination and one for the determination of the monoamines. The electrochemical detection of gamma-aminobutyric acid was determined by a new procedure that utilized a small aliquot of the brain sample prepared for monoamine measurement. This assay was linear and parallel between 6 and 200 ng per 20-microliters injection with 5-aminovaleric acid utilized as an internal standard. Inter-assay variability averaged 5% throughout the assay with gamma-aminobutyric acid values in the gerbil hypothalamus of 344 micrograms/g. The catecholamine assay has been characterized previously and utilizes 3,4-dihydroxybenzylamine as an internal standard with less than 5% variability. Norepinephrine, dopamine, serotonin and 5-hydroxyindoleacetic acid levels in the gerbil hypothalamus averaged 2922, 729, 797 and 272 ng/g, respectively. This new protocol allows a wide range of neurochemicals to be determined and evaluated from the same brain region.
Champney
T H
TH
College of Medicine, Texas A&M University Health Science Center, College Station 77843-1114.
Hanneman
W H
WH
Nichols
M A
MA
D000818:Animals; D001923:Brain Chemistry; D002395:Catecholamines / Q000032:analysis*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D004563:Electrochemistry; D005849:Gerbillinae; D006897:Hydroxyindoleacetic Acid / Q000032:analysis*; D008297:Male; D005680:gamma-Aminobutyric Acid / Q000032:analysis*
D002395:Catecholamines; D006897:Hydroxyindoleacetic Acid; D005680:gamma-Aminobutyric Acid