Parachlorophenylalanine reversal of tranylcypromine effects in depressed patients
B. Shopsin, E. Friedman and S. Gershon
Hospitalized bipolar and unipolar endogenously depressed patients who
showed an antidepressant response to the monoamine oxidase (MAO) inhibitor,
tranylcypromine sulfate, relapsed (ie, depression returned) when relatively
small doses of parachlorophenylalanine (PCPA) were added for brief periods.
Considered together with our findings that PCPA similarly reversed the
antidepressant effects of the tricyclic drug, imipramine hydrochloride,
implications are (1) serotonergic mechanisms are likely involved in the
antidepressant effects of both the tricyclic drugs and MAO inhibitors in
man and (2) this indolamine may also play a role in the endogenous clinical
state of depression.
