ABSTRACT
Objective To investigate the effect and its mechanism of diazoxide on the blood-brain barrier (BBB) of rats after cerebral ischemia/reperfusion (I/R) injury.Methods Sixty Wistar rats were randomly divided into sham operation group,I/R group,and diazoxide pretreatment groups of low,middle,large dose (5,10,20 mg/kg).The I/R models of rats were performed to undergo middle cerebral artery embolism by thread.BBB permeability was estimated by Evans blue (EB) dyeing,transmission electron microscope (TEM) was used to observe the modification of interendothelial tight junction (TJ) of capillaries.The expression of aquaporin-4 (AQP4) in every rat brain tissues was detected by immunity histochemistry technique.Results (1) Compared to sham operation group,the permeability extent of EB were significantly increased by I/R,which was distinctly attenuated in middle and large dose of diazoxide pretreatment rats,while no obvious changes were found between I/R and low dose groups.(2) TEM showed that TJ of the brain tissue opened after I/R injury and no significant opening of TJ was observed in middle and large dose of diazoxide preconditioning groups.(3) Compared to sham operation group,the expression of AQP4 in the brain tissue of the I/R group was apparently increased (P ＜0.01).Compared to I/R group,the expression of AQP4 was apparently increased in middle and large dose pretreatment groups (P ＜ 0.01),and there were no obvious difference between low dose group and the I/R group.Conclusions Preconditioning of ischemia/reperfusion injury with diazoxide protects the blood-brain barrier,which may due to keep the TJ closed and decrease expression of AQP4 protein.
ABSTRACT
Objective To investigate the relationship of serum cholinesterase(CHE) level with the severity and prognosis in patients with acute cerebral infarction. Methods A total of 325 patients with acute cerebral infarction were recruited as patients group,and another 101 healthy sub?jects were selected as control group. Velocity method was employed to detect the level of serum CHE. Patients with acute cerebral infarction were then divided into different groups according to the infarcts diameter and the modified Rankin scale(mRS)at 1 year post stroke. The collected data were analyzed statistically. Results The level of serum CHE in small and medium area infarction group was higher than control group(P<0.01);the level of serum CHE in large area infarction group was lower than control group(P<0.01);the level of serum CHE was negatively correlated with infarct size,NIHSS and the mRS score(r=-0.302,-0.232,-0.455,P<0.001). The level of CHE,age,NIHSS and infarcts diameter was identified as independent influence factors for prognosis of acute cerebral infarction. Conclusion Early phase of serum CHE level is closely related with the infarct size and illness severity index in patients with acute cerebral infarction,which could be an independent factor affecting the prognosis of cere?bral infarction.