Interleukin-10 stimulation of corticotrophin releasing factor median eminence in rats: evidence for dependence upon nitric oxide production

Following treatment with interleukin-10 (IL-10), basal corticotrophin relea sing factor (CRF) levels from rat hypothalamic median eminence (ME) were fo und to be increased. Our data show: (1) the specificity of stimulation of C RF through the use of recombinant IL-10 and its blockage by monoclonal anti -IL-10 antibody; (2) the requirement of NO in this process through the use of N-omega-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor; (3) the blockage of IL-10 stimulated NO production by anti-IL-10 ; and, (4) the presence of IL-10 transcripts in hypothalamic poly A(+) mRNA . These results provide the first evidence of IL-10 acting in the ME to inf luence CRF levels and further support our earlier findings of a potential f or IL-10 in the hypothalamic-pituitary axis. (C) 1998 Elsevier Science Irel and Ltd. All rights reserved.