AMP-activated protein kinase and cAMP response element-binding protein activity are associated with distinct postoperative behavioral changes in rats.

PURPOSE: To explore the association of AMP-activated protein kinase (AMPK) and cAMP response element-binding protein (CREB) activity with distinct postoperative behavioral changes in rats.

METHODS: We performed partial hepatolobectomy in adult rats and aged rats. The learning and memory ability of rats was evaluated by the Barnes maze test on postoperative days 1-4. The expressions of AMPK and phosphorylated CREB (p-CREB) in the CA1 and DG regions of the hippocampus were detected by immunohistochemical assay at 3, 6, 12 and 24 h postoperatively.

RESULTS: Surgery impaired the memory of aged rats but not that of adult rats on postoperative days 2 and 3 (both p < 0.05). Surgery synergistically increased the expressions of AMPK and p-CREB in the CA1 region of hippocampus in aged rats but not in adult rats at 3 and 6 h postoperatively.

CONCLUSION: Our data suggest that surgery induces cognitive impairment in aged rats. Surgery-induced expression of AMPK and p-CREB in the CA1 region of hippocampus may be involved in this cognitive impairment.