Differential anxiety-like behavior, HPA responsiveness, and host-resistance in mice with different circling preference.

Relationships between behavioral sidedness and immune responses in previous studies have differed depending on behavior tests and severity of biological stress in mice. It was necessary to elucidate the psychophysiological mediators that connect behavioral sidedness and immune responses. This study investigated interrelationships among anxiety-like behavior, the HPA axis responsiveness, and host-resistance to bacterial infection. Mice that preferred clockwise circling had lower locomotor activities, higher anxiety-like behavior, and faster activation of the HPA axis than mice that preferred counterclockwise circling. A fast activation of the HPA axis was associated with a higher host-resistance to low dose bacterial infection.