Na. Patel et al., CHRONIC EXPOSURE TO MORPHINE ATTENUATES EXPRESSION OF INTERLEUKIN-1-BETA IN THE RAT HIPPOCAMPUS, Brain research, 712(2), 1996, pp. 340-344
The cytokine, interleukin-1 beta (IL-1 beta), can modulate both immune
and neuroendocrine events. Alteration of IL-1 beta expression by exog
enous factors, such as morphine, may affect the neuro-endocrine-immune
axis. Brain sections from male rats implanted with either morphine or
placebo pellets were stained for IL-1 beta immunoreactivity. The resu
lts showed pronounced attenuation of IL-1 beta immunoreactivity in the
dentate gyrus and the CA1-CA3 fields of the hippocampus in morphine-i
mplanted rats compared to placebo controls. It has been suggested that
the hippocampus is involved in the regulation of hypothalamic activit
y. Attenuation of IL-1 beta expression in the hippocampus by chronic e
xposure to morphine may be one of the mechanisms underlying the neuro-
endocrine-immune modulatory effects of opiate addiction.