The CSF concentrations of CRF, somatostatin and beta-endorphin were determined in nine patients who fulfilled DSM-III criteria for major depression with psychotic features. CSF samples were obtained at baseline in the depressed state, and again after a course of ECT. Concentrations of both CRF and beta-endorphin decreased after ECT, while the concentration of somatostatin increased, although the latter difference did not attain statistical significance. The increase in CSF concentrations of CRF and beta-endorphin in depressed patients is therefore seen to be state-dependent.