Objective:To establish a simple and reproducible animal model of subarachnoid hemorrhage(SAH).Methods:The SAH model was induced by stereotaxic insertion of a cannula through an artifical hole into the prechiasmatic cistern and injection of 300μl autologous arterial blood.The arterial blood pressure

blood gases analysis

and intracranial pressure were monitored

and regional cerebral blood flow(rCBF) was assessed by laser Doppler flowmetry(LDF).A neurobehavioral evaluation was performed at 24 and 48h after SAH.Results:The subarachnoid blood was widely distributed throughout the anterior cranial fossa base

Willis circle and basal cisternal system.There was no statistically significant difference between BP

pH

PaO2 or PaCO2 values of the SAH group and those of the control group(P>0.05).ICP increased rapidly to the maximum 1min after SAH(P<0.05).rCBF decreased rapidly in 1min after SAH

and continued to fall to its nadir in 3min later(P<0.05).Slight neurobehavioral disorders were showed for most rats subjected SAH in 24h

but normalized in 48h after SAH.Conclusion:This new model resembles clinical SAH.It is very reproducible and appropriate for the study on the pathophysiological mechanisms of aneurysmal SAH in the anterior circulation.