Peripheral endotoxin induces hypothalamic immunoreactive interleukin-1 beta in the rat

Interleukin-1 (IL-1) is a polypeptide produced by a variety of cells and contributes to the general host response to inflammation. It displays a wide spectrum of inflammatory, metabolic, physiological, haematopoietic and immunological activities. Brain cells, including neurones, microglia, endothelial cells and astrocytes can all produce IL-1 beta in response to various physiological and pathological stimuli. In this report we show that peripherally administered endotoxin stimulates the appearance of immunoreactive IL-1 beta (IL-1 beta) in the rat hypothalamus as measured by an ultrasensitive, highly specific enzyme amplified immunometric assay for rat IL-1 beta.