Serotonergic 'vulnerability' in affective disorder: a study of the tryptophan depletion test and relationships between peripheral and central serotonin indexes in citalopram-responders.

A double-blind study of the tryptophan depletion (TD) challenge was performed on a sample consisting of 20 patients with a major depressive disorder in clinical remission after citalopram treatment. TD was induced by the intake of 43 g of an amino acid mixture containing the five large neutral amino acids. The control group received the same mixture, to which 2.

Metabolism and menstrual cycle rhythmicity of serotonin in primary headaches.

We investigated the platelet and plasma levels of serotonin and its metabolite, 5-hydroxyindoleacetic acid, in patients suffering from episodic tension-type headache and migraine with and without aura, during a headache-free period. In female subjects, blood samples were drawn during the follicular, ovulatory, and late luteal phases of the menstrual cycle. In tension headache and migraine with aura, the group mean values of serotonin and 5-hydroxyindoleacetic acid in platelets and plasma were significantly increased, but migraine without aura patients' levels were normal.

Effect of picotamide and aspirin, combined or alone, on platelet aggregation in patients with cerebral infarction.

After 7 and 90 days of treatment, we studied the effect of picotamide, a thromboxane synthase inhibitor (450 and 900 mg/day), aspirin (150 mg/day), and aspirin plus picotamide (150 and 450 mg/day respectively) on platelet aggregation, evaluated in platelet rich plasma of 48 patients affected by ischemic stroke. Platelet aggregation, induced by collagen (1.0 and 2.

Platelet models and their possible usefulness in the study of migraine pathogenesis.

Platelets may be linked to migraine. On the one hand they are activated during the migraine attack and thus may participate in the pathogenesis of the disorder (the nature of this activation is still unknown). In order to understand this platelet anomaly, we discuss the data available in the literature.

Decreased collagen-induced platelet aggregation and increased platelet arginine levels in migraine: a possible link with the NO pathway.

We studied whole blood platelet aggregation induced by collagen, platelet activating factor (PAF) and measured basal platelet L-arginine (L-arg) levels, as an indirect index of the nitric oxide (NO) pathway in migraine. Migraine, both with and without aura groups, showed a reduced aggregation to collagen, but not to PAF, compared with control subjects. Platelet L-arg levels were significantly increased in migraine with aura sufferers, whereas the plasma levels were in the same range in migraineurs and controls.