Changes in blood CD4+T and CD8+T lymphocytes in stressed rats pretreated chronically with desipramine are more pronounced after chronic open field stress challenge

•Desipramine (alone or after stress) and stress effect on lymphocytes was explored.•Effects of drug on open field-induced immune response depend on the treatment.•Desipramine affects stress-induced immunosuppression influencing T cell subtypes.•Desipramine reduced IFN-γ producing Th1 and increased IL-10 producing Th2 cells.

The present study examines the influence of a chronic (14 consecutive days) desipramine (10 mg/kg i.p.) pretreatment by itself vs. after chronic (7 consecutive day) open-field (OF) on immune system alterations in response to acute (30 min) OF in Wistar rats (n = 60).Opposing to the effect of desipramine injected alone, the combined pretreatment after chronic OF challenge exerts suppressive effects on peripheral blood T/B, CD4+T-helper/inducer and CD8+T-cytotoxic/suppressor but not NK cell number, decreased interferon-γ/interleukin-10 ratio and thymus weight in the stressed rats. It suggests that chronic stress exposure is important for the immunomodulatory effects of pretreatment with antidepressants.