Microglial sex differences in innate high anxiety and modulatory effects of minocycline.

Microglia modulate synaptic refinement in the central nervous system (CNS). We have previously shown that a mouse model with innate high anxiety-related behavior (HAB) displays higher CD68 microglia density in the key regions of anxiety circuits compared to mice with normal anxiety-related behavior (NAB) in males, and that minocycline treatment attenuated the enhanced anxiety of HAB male. Given that a higher prevalence of anxiety is widely reported in females compared to males, little is known concerning sex differences at the cellular level.