Adrenaline influences the release of interleukin-6 from murine pituicytes:: role of β2-adrenoceptors

In this study, we examined the effect of adrenaline and interleukin-1 beta on interleukin-6 secretion from cultured murine neurohypophyseal cells. Cells were cultured from neurohypophyses of 3- to 5-week-old mice and experiments were performed after 13 days in culture. Interleukin-6 was measured in 24-h samples using a sandwich fluoroimmunoassay. Unstimulated cells released 19 +/- 3 fmol interleukin-6/neurohypophysis/24 h (mean +/- S.E.M., n = 42). Adrenaline and interleukin-1 beta increased the release of interleukin-6 from the cells in a concentration-dependent manner. Incubation with adrenaline (10(-6) M) or interleukin-1 beta (11 pM) induced maximal secretion of interleukin-6, resulting in a 2.2-fold and 19.8-fold increase, respectively (P <0.01). The action of adrenaline (10(-6) M) and interleukin-1 beta (1.1 pM) was examined separately and together. The sum of the effect of the two compounds given alone was significantly less (P < 0.05) than the effect when adrenaline and interleukin-1 beta were given together. We examined the effect of the beta-adrenoceptor antagonist propranolol (3.4 x 10(-6) M), the beta(1)-adrenoceptor antagonist(+/-)-1-[2,3-(Dihydro-7-methyl-1H-inden-4-yl)oxy]-3-[(1-methylethyl)amino]-2-butanol (ICI 118551) (10(-7) M) and the beta(1)-adrenoceptor antagonist atenolol(10(-7) M and 10(-6) M) on the adrenaline-stimulated release of interleukin-6. Propranolol and ICI 118551 completely blocked the action of adrenaline, whereas atenolol was inactive. It is concluded that the stimulatory effect of adrenaline is mediated via beta(2)-adrenoceptors. (C) 1999 Elsevier Science B.V. All rights reserved.