Antidepressant effect of 5-methoxypsoralen: The melatonin synchronizer hypothesis.

5-methoxypsoralen (5-MOP) stimulates pineal melatonin secretion, and a decrease in dark phase melatonin levels has been described in major depression. As exogenous melatonin has shown synchronizer properties, authors hypothesized that giving 5-MOP would have antidepressant properties. Twenty-six inpatients meeting the criteria of major depressive disorders were enrolled in a four-week, double blind trial of 5-MOP versus amitriptyline.

[Plasma tryptophan in a protein controlled diet in depressed patients].

Cerebral serotonin is synthetized from its blood precursor: tryptophan (TRP), an essential amino acid (6). TRP has been extensively studied since serotonine has been reported to be involved in the pathogenesis of depression (9). In one hand, brain serotonin content depends on regulation by plasma large neutral amino acids (LNAA): leucine, isoleucine, valine, tyrosine and phenylalanine that compete with TRP to cross over the blood brain barrier (7, 13).

[Disorders of circadian rhythms in depression].

The authors make a synthesis of studies about circadian rhythms in depression and of hypothesis to explain them. They successively study trials on the phases, on the average levels, on the amplitude of rhythms. They conclude the most significant troubles are, shortening of latency on paradoxical sleep for phases, slump of melatonin levels, blunded amplitude of every parameter.

Trimipramine: acute and lasting effects on sleep in healthy and major depressive subjects.

The acute effects of trimipramine on sleep EEG patterns were investigated in six depressed inpatients and six healthy volunteers. The effects of long-term administration were then assessed in depressed patients after 4 weeks of treatment. Sedative effects of the drug were more pronounced in healthy subjects while sleep parameters of depressed patients seemed less sensitive to the drug.