Anxiety and platelet MAO levels after relaxation training.

The authors measured platelet MAO activity with phenylethylamine and tryptamine substrates in a group of 20 subjects with chronic anxiety before and after they underwent relaxation training. Levels of anxiety were quantified using a self-rating scale. Posttreatment values for anxiety and enzyme activity were significantly lower than pretreatment values. Anxiety and enzyme activity levels were not significantly correlated at any stage of the study.