The Effects of Neuropathic Pain on the State of Glial Cells and Hippocampal Neurogenesis in Old Animals

Abstract

Abstract—We studied the effect of chronic neuropathic pain on the state of microglia and neurogenesis in the hippocampus in old mice. Neuropathic pain was induced by imposing three ligatures on the sciatic nerve of the right hind limb of animals. Testing behavior showed the presence of impaired working memory and locomotor activity in animals with neuropathic pain both in 1 week and 3 weeks after surgery. Behavioral disorders were accompanied by a decrease in hippocampal neurogenesis, as well as an increase in the expression of microglial markers Iba-1 and CD86 in the hippocampus of animals with a ligated sciatic nerve. In addition, the induction of neuropathic pain led to a change in the expression of astroglial markers S100β and GFAP in the hippocampus. The findings suggest that behavioral changes in neuropathic pain are accompanied by changes in the activity of microglia and astroglia, which leads to disruption of neurogenesis and a decrease in cognitive functions.