ABSTRACT
ABSTRACT:Objective To explore role of U0126,the specific inhibitor of ERK signaling pathway,in early brain injury (EBI)and the autophagy of nerve cells in hippocampus area in subarachnoid hemorrhage (SAH). Methods A total of 48 male adult SD rats were randomly divided into control group,SAH group,DMSO+SAH group,and U0126+SAH group,with 12 in each.We established SAH rat model by the puncture of internal carotid artery.The same amount of saline water,DMSO and U0126 solution of 0.5 mL per rat was injected respectively into the rats of different groups 30 min before modeling.The rats were killed at 24 h.To measure brain water content by Wet and dry method after 24 h,the morphological changes of hippocampus CA1 neural cells were observed by microscopy;the expression levels of ERK,Beclin-1 and LC3 were detected by using immunohistochemical method. Results Compared with that in sham group,brain water content increased obviously in SAH model group.The density of surviving neurons in SAH group was significantly lower than that in control group (P<0 .0 5 ).ERK signaling pathway was activated obviously,the expressions of Beclin 1 and LC3-Ⅱ were significantly higher than those in control group (P<0.05).Compared with SAH model group,in U0126 group brain water content increased obviously.Compared with those in SAH group,the density of surviving neurons was significantly lower (P<0.05), ERK signaling pathway was suppressed,the expressions of Beclin-1 and LC3-Ⅱ were significantly lower (P<0.05). Conclusion The U0126,the ERK signaling pathway inhibitor,can inhibit neuron autophagy and increase EBR of SAH.
ABSTRACT
Objective To explore the effect of extracellular regulated protein kinases (ERK) signaling pathway on early brain injury and autophagy of nerve cell in hippocampus area in rats with subarachnoid hemorrhage (SAH). Methods Forty-eight adult male Sprague-Daw-ley rats were randomly divided into sham group, SAH group, SAH+dimethyl sulfoxide (DMSO) group and SAH+U0126 group, with 12 rats in each group. The SAH model was established with puncture of internal carotid artery. The SAH+U0126 group was injected with U0126 0.05 mg/kg;the sham group and SAH group were injected with normal saline, and the SAH+DMSO group was injected with DMSO 30 min-utes before modeling. They were sacrificed 24 hours after modeling. The brain water content was measured with wet and dry method. The morphology changes of neural cells in hippocampus CA1 were observed by HE staining. The expression of phosphorylation ERK (p-ERK), Beclin-1 and LC3-Ⅱwere detected with immunohistochemical method and Western blotting. Results Compared with the sham group, the brain water content increased (P0.05). Conclusion The activation of ERK signaling pathway may alleviate early brain injury after SAH by regulation of autophagy.