Thus far, there are only a few animal models for delirium research. One of the barriers to advancing work on the basic mechanisms of postoperative delirium is the lack of animal model(s). However, at the present time, postoperative delirium remains a wholly clinical diagnosis its causes, neuropathogenesis and targeted intervention(s) remain largely to be determined. Postoperative delirium, an acute, transient, fluctuating disturbance in attention, cognition, and level of consciousness, is a common (15–53%) postoperative complication 1, 2, 3, and it can lead to 2- to 20-fold increase in mortality 4, long term functional impairment, postoperative cognitive dysfunction, and increased costs of medical care. These findings suggest that we could use a battery of behavior tests to establish a mouse model to study postoperative delirium. Cyclosporine A selectively ameliorated the Anesthesia/Surgery-induced reduction in ATP levels, the increases in latency to eat food, and the decreases in entries in the novel arm. The composite Z scores quantitatively demonstrated the Anesthesia/Surgery-induced behavior impairment in mice. Anesthesia/Surgery selectively impaired behaviors, including latency to eat food in buried food test, freezing time and time spent in the center in open field test, and entries and duration in the novel arm of Y maze test, with acute onset and various timecourse. Cyclosporine A, an inhibitor of mitochondria permeability transient pore, was used to determine potential mitochondria-associated mechanisms of these behavioral changes. The mice were tested at 24 hours before and at 6, 9 and 24 hours after the Anesthesia/Surgery. We therefore set out to employ a battery of behavior tests, including natural and learned behavior, in mice to determine the effects of laparotomy under isoflurane anesthesia (Anesthesia/Surgery) on these behaviors. However, its neuropathogenesis remains largely unknown, partially owing to lack of animal model(s).
Postoperative delirium is associated with increased morbidity, mortality and cost.