Figure 2.

mRNA expression in the hypothalamus of pro-inflammatory mediators and markers of HPA axis activation 90 min after induction of novel environment stress or in unstressed controls in young and old male rats. (A) Stress induced an enhanced expression of interleukin (IL)-6 only in the aged rats. (F) The expression of CRH (corticotropin releasing hormone), on the contrary, was significantly increased after psychological stress only in the young rats while remaining unchanged in the aged group. (B–E,G) The other investigated parameters NF-IL6 (nuclear factor interleukin 6), SOCS3 (suppressor of cytokine signaling 3), COX2 (cyclooxygenase-2), mPGES (microsomal prostaglandin E synthase) and POMC (proopiomelanocortin) were not affected by treatment or age. Main effect of treatment not indicated; ^*main effect of age; ^#post-hoc stress different from control; ^*, ^#P < 0.05. Control young n = 4, stress young n = 4, control old n = 5, stress old n = 5.