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Biomedical subjects

G J Naylor

Publications and source records attributed to G J Naylor.

At least 73 records · Page 4Linked to original sources

Lithium and erythrocyte membrane cation carrier studies in normal and manic depressive subjects.

Changes in the erythrocyte membrane cation carrier following lithium ingestion in normal human subjects were studied; ouabain sensitive potassium influx fell significantly during the lithium treated phase. Lithium was fed to rats and no change in erythrocyte Na-K ATPase was shown. These findings contrast with studies of lithium in manic depressive psychosis. The fluctuations in the erythrocyte membrane cation carrier were studied in 5 normal subjects over 12 weeks and the correlations between the parameters calculated. The erythrocyte sodium concentration correlated positively with the ouabain sensitive potassium influx. This too contrasts with findings in manic depressive psychosis.

Adenosine Triphosphatases↗

Changes in the erythrocyte sodium pump with age.

Various estimations of the erythrocyte sodium pump were determined in 18 female and 11 male adult subjects. In the female group, but not in the male group, the sodium concentration increased with age; the erythrocyte active transport decreased and passive transport increased with age and could account for the observed change in erythrocyte sodium concentration with age. The erythrocyte Na-K ATPase decreased with age in the females and this could account for the observed change in active transport.

Adenosine Triphosphatases↗

Erythrocyte membrane cation carrier, relapse rate of manic-depressive illness and response to lithium.

Biochemical studies of manic-depressive psychosis usually correlates biochemical findings with current affective state and hence any significant findings could be secondary to mood change. The present study attempts to correlate measures of the erythrocyte membrane cation carrier with clinical events, remote in time from the biochemical assay. Eprythrocyte sodium concentration, ouabain-sensitive potassium influx and Na-K ATPase were estimated in 11 patients before and after the cross-over point in a 2-year double blind clinical trial ratio tended to suffer most episodes of affective illness in the 2 years. Patients who had a low initial Na-K ATPase or a high initial flux sodium ATPase ratio, or in whom this ratio fell most with lithium or whose Na-K ATPase rose most with lithium, clinically responded best to lithium.

Adenosine Triphosphatases↗

Erythrocyte membrane cation carrier in mania.

Erythrocyte sodium and potassium concentrations, erythrocyte membrane ATPase (Na-K specific and non-specific) and the rate of potassium influx into erythrocytes (ouabain-sensitive and insensitive) were estimated in a group of female patients suffering from mania and repeated on about two thirds of them when they had recovered. With recovery there was a statistically significant increase in the erythrocyte ouabain-sensitive potassium influx. The other parameters showed no significant overall change with recovery but the initial severity correlated significantly and negatively with the change in erythrocyte Na-K ATPase with recovery. The changes that occurred in the erythorcyte sodium concentration and Na-K ATPase activity were not random since they correlated significantly with changes in the active potassium influx.

Adenosine Triphosphatases↗

A biochemical study of short-cycle manic-depressive psychosis in mental defectives.

Four mentally defective patients who were suffering from short-cycle manic-depressive psychosis were each studied under metabolic ward conditions for about six months. Weekly estimations of erythrocyte Na-K ATPase activity, ouabain sensitive potassium influx, sodium concentration, whole blood cell ATP concentration and blood haematocrit were made. The findings in each patient differed, but the erythrocyte Na-K ATPase activity, sodium and ATP concentration appeared to show cyclic changes related to, though out of phase with, the clinical state.

Adenosine Triphosphatases↗

Plasma tryptophan concentration in depressive illness and mania.

Total and free plasma trytophan levels were measured in depressive and manic patients before and after recovery. No change was found in total or free plasma trytophan concentration on recovery from depressive illness. Free plasma tryptophan levels were higher in recovered manics than in active manics, and a group of four manic patients tested before and after recovery showed a significant increase in free plasma tryptophan concentration on recovery.

Adult↗

Plasma concentrations of protriptyline and clinical effects in depressed women.

We studied the relationship between side effects, clinical outcome and the drug plasma levels in 28 female depressed patients treated with protriptyline. After 3 1/2 weeks treatment, patients with plasma levels within a median range (630 to 900 nmol/l) showed better responses to the drug than patients with plasma levels outside this range. There were no statistically signficant correlations between plasma levels and side effect scores or 'corrected' side effect scores (scores after subtracting pretreatment values) for the group at any time after starting the treatment. But we found positive correlations between plasma levels and 'corrected' side effect scores for the neurotic subgroup after 14 and 21 days of treatment. Other correlations between plasma levels and side effect scores were non-significant.

Adjustment Disorders↗

Whole blood adenosine triphosphate in manic-depressive illness.

Whole blood cell ATP concentration was estimated in a group of manic and depressed patients and in a group of normal subjects. There were no significant differences between patient and control groups, nor in the patient groups were there any significant changes with recovery.

Adenosine Triphosphate↗

Trial of digoxin in mania.

A suggestion that mania is associated with an increased membrane transport of sodium has been investigated in a double-blind trial of a specific Na-K A.T.P.ase inhibitor (digoxin) in twelve female inpatients with mania. Digoxin had no effect.

Biological Transport↗

Lithium in non-manic-depressives: antiaggressive effect and red blood cell lithium values.

Lithium was given to eight aggressive, non-manic-depressive female defectives in a doubleblind placebo-controlled study. The group as a whole showed a reduction in aggression scores while on lithium (p greater than 0.01): three patients became less aggressive,one became worse and two were unchanged. Both affective and predatory aggression seemed to be reduced. Two patients had to be withdrawn from the trial at an early stage because of the development of neurotoxicity.

Adult↗