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Biomedical subjects

A Coppen

Publications and source records attributed to A Coppen.

188 records · Page 11Linked to original sources

Lymphocyte beta-adrenergic receptor density of patients with recurrent affective illness.

The binding characteristics of (-)3-[125I]iodocyanopindolol, a high specific activity antagonist for the lymphocyte beta-adrenoceptor, were determined in a group of euthymic lithium-treated patients and controls. There was a statistically significant reduction (less than 20%) in the density of beta-adrenoceptors in a group of 56 lithium-treated patients. Division of this group of patients into the unipolar and bipolar distinction indicated that the abnormality was based mainly in the bipolar group of patients. The unipolar patients with an endogenous form of the illness also showed this abnormality. Reduced beta-adrenoceptor density may be associated with endogenous affective illness. However, the results must be interpreted with caution since lymphocyte fractions prepared for beta-adrenoceptor assays can be contaminated with platelets and since platelets have been reported to have beta-receptors then a proportion of the total binding could be associated with platelet beta-adrenoceptors rather than with lymphocyte beta-adrenoceptors.

Adult↗

Folic acid enhances lithium prophylaxis.

A double-blind trial was carried out to investigate the effect on affective morbidity of a daily supplement of 200 micrograms folic acid or a matched placebo in a group of 75 patients on lithium therapy. During the trial the patients with the highest plasma folate concentrations showed a significant reduction in their affective morbidity. Patients who had their plasma folate increased to 13 ng/ml or above had a 40% reduction in their affective morbidity. It is suggested that a daily supplement of 300-400 micrograms folic acid would be useful in long-term lithium prophylaxis.

Adult↗

Seasonal variations in the dexamethasone suppression test.

One hundred and fifty-six patients from Epsom (U.K.) and Brussels, all suffering from major depressive disorder, were tested on the dexamethasone suppression test. Post-dexamethasone cortisol concentration in the plasma was found to be much lower in the winter months (November to February) than in the rest of the year.

Adult↗

Depression and tetrahydrobiopterin: the folate connection.

Total biopterin, neopterin and creatinine were measured in spot urine samples from affective disorder patients on lithium therapy and control subjects. Folic acid was also measured in plasma in a sample of the patients. The mean neopterin: biopterin ratio was significantly higher in the 76 patients (3.2 +/- 0.5) than in the 61 controls (1.8 +/- 0.1). In female patients biopterin levels were significantly lower than in controls. In the control groups there was a significant correlation between the molar concentration of neopterin and biopterin. No such correlation was found in the patients. These data indicate that tetrahydrobiopterin (BH4) biosynthesis is reduced in this group. A significant positive correlation was found between plasma folate and urinary biopterin. It is suggested that folate deficiency may impair the synthesis of BH4, a cofactor essential for the synthesis of 5-HT and other monoamines that are involved in the pathogenesis of affective disorders.

Adult↗