Sleep deprivation and imipramine binding sites in depressed patients and healthy subjects.

The influence of sleep deprivation on 3H imipramine binding was investigated in blood platelets of 32 depressed patients and 15 healthy subjects. The effect of sleep deprivation was not statistically different in either group. Changes of Bmax associated with sleep deprivation were compensated for by reciprocal changes of Kd in the group of patients, suggesting altered regulatory mechanisms. A comparison of binding characteristics of responders and nonresponders to sleep deprivation revealed no difference between groups. If the patients were divided by a biological criterion (number of binding sites), a prediction of clinical response to sleep deprivation was possible.