Evidence of a possible role of altered angiotensin function in the treatment, but not etiology, of depression

Background: Angiotensin-converting enzyme inhibitors are reportedly effecti ve in the treatment of depression; furthermore, antidepressants decrease an giotensin function. It appears therefore that reduced angiotensin function may be important in the treatment of depression. The aims of this study wer e to elucidate the actions of antidepressants on :angiotensin receptors; to investigate the antidepressant potential of an angiotensin antagonist; and to study angiotensin receptors in depressed puerperal women. Methods:The effects of antidepressant drugs on angiotensin receptors and th e relationship between mood and platelet receptors in puerperal women were investigated using radioligand binding. The antidepressant potential of the angiotensin antagonist losartan was assessed using the mouse forced swim t est. Results: Desipramine, but neither fluoxetine nor tranycypromine, displaced angiotensin from its receptor; however, there was no significant relationsh ip between receptor number and depressed mood. In the forced swim test losa rtan was shown to possess antidepressant like activity. onclusions: These findings indicate that antidepressants differ in the mech anism by which they. reduce angiotensin function, but the link between anti depressants and angiotensin is reiterated by the demonstration that losarta n possesses antidepressant like activity. There is, however, no evidence of abnormal angiotensin receptors in women with depressed mood postpartum. Bi ol (C) 1999 Society of Biological Psychiatry.