A neuroendocrine study of the mechanism of action of ECT.

To test the possibility that the antidepressant action of ECT is due to an enhanced responsiveness to the stimulation of monoamine receptors, we have measured pituitary hormone responses to test doses of clonidine and methylamphetamine in depressed patients before and after a course of ECT. There was no enhancement of the growth hormone response to either drug following a course of ECT. Cortisol responses to methylamphetamine were enhanced, but probably this was secondary to the partial or complete recovery of the patients. Further neuroendocrine studies of the mechanism of action of ECT in man are needed.