Mjm. Vandermeer et al., EFFECTS OF CYTOKINES ON PITUITARY BETA-ENDORPHIN AND ADRENAL CORTICOSTERONE RELEASE IN-VITRO, Cytokine, 8(3), 1996, pp. 238-247
We investigated the effects of recombinant human IL-1 alpha, -1 beta,
-2, -6 and TNF on the in vitro secretion of beta-endorphin-immunoreact
ivity (beta E-IR) by the rat anterior and neurointermediate lobes (AL
and NIL, respectively) and of B by the rat adrenal gland. Isolated AL
and NIL cells were incubated for 2 h with cytokines (1 pg/ml-1 mu g/ml
), CRH (5.10(=10) M) or with cytokines in combination with CRH (AL cel
ls), isolated adrenal cells were incubated for 2 h with cytokines, ACT
H (25 pg/ml) or with cytokines in combination with ACTH. Furthermore,
AL, NIL and adrenal tissue fragments were superfused for 30 or 60 min
with cytokines (10 and/or 100 ng/ml). Incubation of AL, NIL and adrena
l cells and superfusion of these tissues with cytokines had no signifi
cant effect on beta E-TR and B release. However, there are some except
ions: incubation of AL cells with IL-2 increased CRH-induced beta E-IR
release, incubation of NIL cells with IL-2 induced an increase of bas
al beta E-IR release. ACTH-induced B secretion was reduced after co-in
cubation of adrenal cells with TNF and after prolonged (6 h) superfusi
on of adrenal tissue with TNF, and finally, prolonged (6 h) superfusio
n of adrenal fragments with IL-1 beta increased basal B release. Taken
together, these data suggest that the acute activation of the pituita
ry-adrenal axis of rats by administration of cytokines (at least IL-1,
IL-6 and TNF) in vivo is not mediated by a direct action of these cyt
okines at the level of the pituitary and/or adrenal gland. (C) 1996 Ac
ademic Press Limited