Abstract: ObjectiveTo investigate the effects of fasudil hydrochloride on learning and memory, and the autophagy in hippocampal CA1 neurons in subarachnoid hemorrhage (SAH) rats. MethodsFifty-four male Sprague-Dawley rats were randomly divided into sham group (n=18), SAH group (n=18) and drug group (n=18). Subarachnoid hemorrhage model was established with internal carotid artery puncture. The drug group was injected fasudil hydrochloride 10 mg/kg intraperitoneally after modeling per 24 hours, while the sham group and SAH group were injected the same volume of saline. They were tested with shuttle box test 6, 24 and 72 hours after intervention, then the hippocampal CA1 area was stained with HE and immunohistochemistry to observe the morphology of cells and the expression of Beclin-1 and microtubule-associated protein 1 light chain 3 II (LC3-II). ResultsCompared with the sham group, the frequence of avoidance decreased in SAH group at each time point (P<0.05), while the avoidance reaction time increased (P<0.05); the survival of neurons in hippocampal CA1 area decreased (P<0.05), and the expression of Beclin-1 and LC3-II increased (P<0.05). Compared with SAH group, the frequence of avoidance increased in the drug group at each time point (P<0.05), while the avoidance reaction time decreased (P<0.05); the survival of neurons in hippocampal CA1 area increased (P<0.05) and the expression of Beclin-1 and LC3-II increased further (P<0.05). ConclusionFasudil hydrochloride can improve learning and memory ability and protect neurons from damage, which may associate with the excess of autophagy activation in hippocampal CA1 areas in SAH rats.

Key words: subarachnoid hemorrhage, fasudil hydrochloride, learning and memory, autophagy, rats