Prolonged increase of corticosterone secretion by chronic social stress does not necessarily impair immune functions.
The influence of a chronic social stress upon immunity was investigated in Wistar rats, submitted for four weeks to two different behavioral situations, balanced in a factorial design: housing with three females and membership rotation. The combination of these two factor led to adrenal enlargement (43.3%), thymus involution (39.5%) and increased basal corticosterone levels, all indices of activation of the hypothalamic-hypophysis-adrenal axis. However, neither natural killer cell activity, splenocyte reactivity to mitogen nor the rate of spontaneous development of antibodies against Mycoplasma pulmonis, a common pathogen of the respiratory tract, were changed in the endocrine activated animals. Analysis of the data on kinetics of stress at 1, 7 and 28 days after the initial mixing of the animals gave the same results. These data question the immunosuppressant activity usually conferred to corticosteroids, at least when adrenal hyperactivity is induced by chronic environmental stressors.
Klein
F
F
Laboratoire de Psychobiologie des Comportements Adaptatifs INSERM U259-INRA, Université de Bordeaux II, France.
Lemaire
V
V
Sandi
C
C
Vitiello
S
S
Van der Logt
J
J
Laurent
P E
PE
Neveu
P
P
Le Moal
M
M
Mormède
P
P
D000311:Adrenal Glands / Q000473:pathology; D000818:Animals; D000907:Antibodies, Bacterial / Q000096:biosynthesis; D002908:Chronic Disease; D003345:Corticosterone / Q000378:metabolism / Q000502:physiology*; D005260:Female; D007694:Killer Cells, Natural / Q000502:physiology; D008213:Lymphocyte Activation / Q000502:physiology; D008297:Male; D009174:Mycoplasma / Q000276:immunology; D009929:Organ Size; D051381:Rats; D011919:Rats, Inbred Strains; D013154:Spleen / Q000276:immunology / Q000473:pathology; D013315:Stress, Psychological / Q000276:immunology* / Q000473:pathology / Q000503:physiopathology*; D013950:Thymus Gland / Q000473:pathology
D000907:Antibodies, Bacterial; D003345:Corticosterone