Sex-dependent role of Interleukin-1 signaling in emotional and cognitive behaviors in mice: Phenotyping male and female IL1-R1 null mutant mice

SEX-DEPENDENT ROLE OF INTERLEUKIN-1 SIGNALING IN EMOTIONAL AND COGNITIVE BEHAVIORS IN MICE: PHENOTYPING MALE AND FEMALE 1L1-R1 NULL MUTANT MICE by Jennifer A. Johnson Adviser: Adjunct Associate Professor Susan D. Croll IL1-R1 null mutant mice (IL1-R1 KO) have reduced signaling in the interleukin-1 (IL-1) pathway, making them a convenient model for testing the importance of IL-1 in either the development or maintenance of mouse behaviors. Prior research has revealed impaired cognitive and emotional processes in adult male IL1-R1 KO mice, including impaired spatial learning and memory and decreased anxiety with associated impairments in hippocampal cell proliferation and signal transmission. The current studies explored the neuroanatomy and behavioral phenotype of both male and female IL1-R1 KO mice. An array of behavioral tests was administered, including retesting at an older age for cognitive and emotional behaviors. Animals were sacrificed and their brains were measured for neuroanatomical abnormalities, cell population densities, and vascular proliferation. The results were consistent with prior findings of impaired spatial learning and memory performance for male IL1-R1 KO animals, as well as reduced anxiety-type responses in multiple behavioral tests. Female IL1-R1 KO mice were less affected, and showed no behavioral impairment in the Morris Water Maze (MWM). The findings also revealed an increased depressive-type behavior in the Porsolt Forced-Swim test