Mitogen stimulated rise of intracellular calcium concentration in single T lymphocytes from patients with major depression is reduced.
1. The authors investigated the signal transduction in T-lymphocytes as a peripheral model for central neurons. 2. Intracellular free calcium concentration [Ca2+]i was measured using fura 2 in T-lymphocytes from 6 patients with major depression during and after depression and from 6 healthy controls. Patients were treated with interpersonal therapy (IPT) but not with psychotropic medication. 3. Phytohemagglutinin (PHA) triggers an oscillatory [Ca2+]i signal in human T-lymphocytes. This implies two mechanisms for [Ca2+]i regulation: inositol phophate (IP) mediated release from intracellular stores and [Ca2+]i influx from the extracellular medium. 4. PHA stimulates 49% of T cells from controls but only 17% of T cells from depressed patients. This finding explains previous results from cells in suspension indicating that [Ca2+]i signals after PHA-stimulation are reduced in cells from depressed patients. 5. Cells from depressed patients show less [Ca2+]i oscillations. Normal oscillation patterns are restored after clinical recovery from depression. 6. Thus altered [Ca2+]i oscillations in T-lymphocytes are a state phenomenon and may give us clues where to search for altered cellular mechanisms during depression.
Vollmayr
B
B
Department of Psychiatry, Central Institute of Mental Health, Mannheim, Germany.
Sulger
J
J
Gabriel
P
P
Aldenhoff
J B
JB
D000328:Adult; D002118:Calcium / Q000378:metabolism*; D002138:Calibration; D003866:Depressive Disorder / Q000378:metabolism* / Q000628:therapy; D005260:Female; D016257:Fura-2; D006801:Humans; D006854:Hydrocortisone / Q000378:metabolism / Q000494:pharmacology; D008297:Male; D008875:Middle Aged; D008934:Mitogens / Q000494:pharmacology*; D010835:Phytohemagglutinins / Q000494:pharmacology; D011569:Psychiatric Status Rating Scales; D015398:Signal Transduction / Q000187:drug effects; D013601:T-Lymphocytes / Q000187:drug effects / Q000378:metabolism*
D008934:Mitogens; D010835:Phytohemagglutinins; D002118:Calcium; D016257:Fura-2; D006854:Hydrocortisone