title: Red cell ouabain-sensitive Na+-K+-adenosine triphosphatase: a state marker in affective disorder inversely related to plasma cortisol.
abstract: Ouabain-sensitive Na+-K+-stimulated ATPase was measured in red cell membranes using a spectrophotometric assay. The mean enzyme level in patients in the depressed state (1.2 nM/mg protein per min +/- 0.18 SEM) was lower lower than that in well-state patients (2.0 +/- 0.26) and hypomanic patients (2.4 +/- 0.31). Lithium treatment itself did not alter ATPase levels. Levels in patients in the well state were not significantly different from controls and thus ATPase does not constitute a "trait" marker for affective illness. Plasma cortisol level was higher in well-state patients (15.9 micrograms/dl +/- 1.46) than in controls (11.5 +/- 0.75). There were no significant differences in cortisol in these single morning samples during different mood states. Cortisol level correlated negatively with ATPase level in the total group of patients (r = 0.42, p less than 0.005), especially in those who were euthymic. These data indicate a relationship between cortisol and ATPase levels in affectively ill patients. Ouabain-sensitive NaK ATPase may be useful as an indicator of state in affective illness; plasma cortisol may be continuously elevated in some individuals with affective disorder.
mesh_terms: D000328:Adult; D000341:Affective Disorders, Psychotic / Q000175:diagnosis / Q000201:enzymology* / Q000235:genetics; D000929:Antidepressive Agents, Tricyclic / Q000627:therapeutic use; D001714:Bipolar Disorder / Q000201:enzymology; D003866:Depressive Disorder / Q000201:enzymology; D004910:Erythrocyte Membrane / Q000201:enzymology*; D004912:Erythrocytes / Q000201:enzymology*; D005260:Female; D005819:Genetic Markers; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008094:Lithium / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D010042:Ouabain; D000254:Sodium-Potassium-Exchanging ATPase / Q000097:blood* / Q000235:genetics
chemical_list: D000929:Antidepressive Agents, Tricyclic; D005819:Genetic Markers; D010042:Ouabain; D008094:Lithium; D000254:Sodium-Potassium-Exchanging ATPase; D006854:Hydrocortisone