Attempt to demonstrate an in vivo effect of mianserin hydrochloride on erythrocyte Na+‐K+‐ATPase activity and cyclic AMP concentration.

Abstract

1. There is evidence that erythrocyte Na+‐K+‐ATPase activity and erythrocyte cyclic AMP change on recovery from a depressive illness. Mianserin is a recently introduced antidepressant but its mode of action is unknown. The present study was therefore designed to investigate in vivo the effect of mianserin on erythrocyte Na+‐K+‐ ATPase and cyclic AMP. 2. Biochemical estimations were made on blood from depressed patients before beginning either mianserin or matched placebo treatment, after 1 week, and again after 2 weeks' treatment. 3. Neither the erythrocyte Na+‐K+‐ATPase, nor the erythrocyte cyclic AMP concentration, changed significantly in either the mianserin‐ or the placebo‐treated group. 4. The study sheds no light on the possible mechanism of action of mianserin.