EFFECT OF INTRACEREBROVENTRICULAR INJECTION OF IL-1βON GENERATION OF IMMUNO-SUPPRESSIVE FACTOR IN LYMPHOCYTES IN STRESSED MICE

our previous work showed that a suppressive factor( a protein with largemolecular weight in serum was induced by restraint stress in mice and rats,which suppressed Con Ainduced lymphocyte proliferation.It was also found that the generation of serum suppressive factorwas under control of the central nervous system.Our further study showed thatintracerebroventricular(icv )injection of interleukin 1 receptor antagonist(IL-1Ra)antagonised thegeneration of serum suppressive factor induced by restraint stress and icv injection of interleukin-1β(IL-1β)increased the generation of the suppressive factor.Our experiment also showed that the serumsuppressive factor induced by restraint stress was first made in lymph tissue and then released intoblood.The present work was designed to investigate the role of IL-1 in the brain in generation of thesuppressive factor in lymph node in mice.Icv injection of IL-1β( 1 pg/mouse) was shown tosignificantly increase the generation of the suppressive factor in lymph node.Icv injection of IL-1Ra,however ,antagonised generation of the suppressive factor.In mice without restraint stress,both thesuppressive factor in serum and in lymph node were found to be induced in dose-dependent manner byicv injection of IL-1β.Taken together,these results suggest that IL-1β in brain played a veryimportant role in generation of the suppressive factor in lymph node.The positive correlation betweenthe suppressive action of lymph node and of serum added to the evidence that lymph tissue is probablythe source of the serum suppressive factor.