Protective effects of hirudin on acute experimental intracerebral hemorrhage / 中国中药杂志

<p><b>OBJECTIVE</b>To explore the protective effects of hirudin on acute experimental intracerebral hemorrhage (ICH) by observing the changes of histologic pathology and brain water content as well as GFAP-positive cells in the perihematomal brain regions.</p><p><b>METHOD</b>The models of rat ICH were made with infusion of autologous blood into the right neucleus caudatus. The rats were divided randomly into control group, intracerebral hemorrhage group and treating group with hirudin. Brain water content was measured, and pathological and GFAP changes were observed.</p><p><b>RESULT</b>The pathological impairation after ICH were gradually deteriorated and peaked at the third day. Brain water content after ICH was gradually increased and obviously after one day(P < 0.05) and peaked at the third day. GFAP-positive cells were gradually increased and peaked at the seventh day after ICH. In the treating groups, the pathological impairation and brain water content as well as the GFAP-positive cells were decreased as compared to those in the intracerebral hemorrhage group and the control group. And the positive correlation between GFAP-positive cell numbers and brain water content were shown by linear regression.</p><p><b>CONCLUSION</b>The local administration of hirudin, a special inhibitor of thrombin, has protective effects within the first week after ICH.</p>

Effect of gap junction on permeability of blood-brain barrier in rats after cerebral ischemia- reperfusion / 中华神经科杂志

Objective To investigate the possible mechanism of the gap junctional influence on the change in permeability of the blood-brain barrier(BBB)after reperfusion subsequent to cerebral ischemia.Methods In the test laser scanning confocal microscope(LSCM)was used to investigate the change of Cx43 levels and distribution.The MCAO/R model was induced using intraluminal suture technique first described by Longa with a little modification.A total of 60 Wistar rats were divided into 4 groups:the sham-operation group,control group,octanol-treatment group and DMSO vehicle control group. Control group were further divided into seven subgroups at different time points of reperfusion after middle cerebral artery occlusion.To observe the change in permeability of BBB,Evans blue(EB)in the brain tissue was surveyed by the means of EB fluorescent quantitation.Octanol-treatment group and DMSO vehicle control group were done at the point of the peak of permeability of BBB.Octanol,the specific blocker for gap junctions(GJ)was used in an intervention study.To compare the amount of EB with the same point of groups,the influence of octanol on BBB permeability was investigated.Results At 3 h of reperfusion after cerebral ischemia for 2 h,the permeability of BBB began to increase,reached the peak at 24 h of reperfusion and was still elevated at 72 h.The Cx43 expression formed into bigger plague and remained linear disposition in the penumbra after reperfusion subsequent to cerebral ischemia.Octanol group was done at 24 h of reperfusion after cerebral ischemia.The amount of EB of octanol group((4.924?0.296)?g/g)was significantly lower than that of corresponding operation control group(5.543?0.506)?g/g.Conclusions (1)Cx43 expression is concentrated around vessels in brain.The Cx43 forms into bigger plague and the function maybe strengthens after reperfusion.Gap junction might aggravate the disruption of BBB.(2) Octanol,the specific blocker of gap junctions,could effectively prevent the permeability of BBB from increasing and has a protective effect on BBB.