an investigation of a possible neurochemical basis for this behaviour was made by using sensitive radioenzymatic and microfluorimetric assays to estimate the concentrations of the catecholamines and of the dopamine metabolites homovanillic acid ( hva ) and 3,4-dihydroxyphenyl-acetic acid ( dopac ) in different brain regions .
C0007412
catecholamines
C0013030
dopamine