THE ROLE OF PTERINS IN DEPRESSION AND THE EFFECTS OF ANTIDEPRESSIVE THERAPY

Urinary excretion of neopterins (N) and biopterins (B) was measured in 48 patients with depression before and after treatment with placebo, antidepressants, or electroconvulsive therapy (ECT), and in 26 healthy control subject. Patients prior to and after treatment has a signific antly greater neopterin/biopterin (N:B) ratio than control subjects. T here wa a significant correlation between NB: ratios and severity of d epression and plasma cortisol. As a raised N:B ratio implies failure t o convert neopterin to biopterin, it is possible that reduced availabi lity of tetrahydrobiopterin, the essential cofactor for the formation of noradrenaline, serotonin and dopamine, may exert rate-limiting cont rol over the synthesis of monoamines implicated in the pathogenesis of depressive illness.