Effect of adrenalectomy and stress on interleukin-1 beta-mediated activation of hypothalamic corticotropin-releasing factor mRNA.

We have investigated the effect of (a) stress and (b) steroid feed-back on the interleukin-1 beta (IL-1 beta)-mediated increase of corticotropin-releasing factor (CRF) mRNA in the hypothalamic paraventricular nucleus. Both IL-1 beta and stress resulted in increased levels of CRF mRNA and when both were given together, the combination resulted in an additive effect on the increase in CRF transcripts. The effect of IL-1 beta was blunted by adrenalectomy, but returned when a replacement dose of dexamethasone was administered. The IL-1 beta-induced increase in CRF mRNA is dependent on the presence of circulating glucocorticoids, and its mechanism of action on CRF mRNA appears to be distinct from that activated in response to stress.