INCREASED NADPH-DIAPHORASE REACTIVITY AND CYTOKINE EXPRESSION IN DORSAL-ROOT GANGLIA IN ACQUIRED-IMMUNODEFICIENCY-SYNDROME

We studied lumbosacral dorsal root ganglia (DRGs) from 10 patients wit h acquired immunodeficiency syndrome (AIDS) and five controls using im munocytochemistry, in situ hybridization and NADPH-diaphorase (NADPHd) histochemistry, Human immunodeficiency virus (HIV)-1 RNA was detected in five AIDS cases, acid HIV-1 p24 antigen was found in four of these patients. The densities of nodules of Nageotte (nN), macrophages and major histocompatibility complex-class II-positive cells were signific antly increased in the DRGs of AIDS patients compared to controls, Cyt omegalovirus antigen was observed in the DRGs of four AIDS cases and o ne control, but without its presence being related to neuronal degener ation. Furthermore, we detected tumor necrosis factor, interferon-gamm a, interleukin (IL)-1 beta, and IL-6 in the DRGs from AIDS patients, U sing NADPHd histochemistry, we showed that the number of NADPHd-positi ve neurons was significantly increased in the DRGs of AIDS patients co mpared to controls, implying upregulation of nitric-oxide (NO) product ion in AIDS DRGs. Generally, there were increased numbers of nN in DRG s which contained more NADPHd-positive neurons. Additionally, immunore activity for an inducible form of NO synthase was detected in intersti tial cells in AIDS DRGs. These results suggest that reactive inflammat ion, including the production of cytokines, occurs in the DRGs of AIDS patients and that excessive production of NO may be related to neuron al degeneration in AIDS DRGs.