Study On Efficacy Of Rt-PA Thrombolytic In Diabetic Rats With Cerebral Infarction In Different Time Windows

Objective By observing changes of rats’ behavior, calculating the volume of cerebral infarction,and determining the hemorrhagic transformation (HT), the efficacy of rt-PA intravenousthrombolysis in rats with acute cerebral infarction and type2diabetes in different time windowswas explored.Methods90adult male Wistar rats weighting200-250g were selected. Rats with type2diabetes model were induced by the application of streptozotocin(STZ) and cerebral infarctionthrombolysis models were prepared with the thromboembolism method. Then the rats wererandomly divided into2h thrombolysis group (group A),3h thrombolysis group (group B),4hthrombolysis group (group C) and control group (group D). The first three groups were givenrt-PA thrombolysis at2h,3h,4h after cerebral infarction respectively and the control group wasgiven equal volume of normal saline. The neurologic deficit was scored by observing rats’behavior changes; the volume of cerebral infarction was calculated by observing TTC stainingand the hemorrhagic transformation (HT) was determined by observing HE staining after thecerebral infarction rats waking up from anesthesia and24hours after cerebral infarction.Results1.Neurological deficits degrees of the2h thrombolysis group and the3h thrombolysisgroup were no significant difference after24hours of cerebral infarction (P>0.01), but werelower than4h thrombolysis group and the control group after24h of cerebral infarction and thecerebral infarction rats waking up from anesthesia (P <0.01); Neurological deficits degrees ofthe4h thrombolysis group and the control group after24hours of cerebral infarction andcerebral infarction rats waking up from anesthesia were no significant difference (P>0.01).2.The infarct volumes of the2h thrombolysis group and3h thrombolysis group after24hoursof cerebral infarction and the cerebral infarction rats woke up from anesthesia were nosignificant difference (P＞0.01), but were smaller than the4h thrombolysis group and control group after24hours of cerebral infarction （P＜0.01). The infarct volumes of the4hthrombolysis group and control group were no significant difference after24hours of cerebralinfarction（P＞0.01).3. rats presented hemorrhagic transformation in the2h thrombolysis group and hemorrhagictransformation rate was16.7%(2/12);4presented hemorrhagic transformation in the2hthrombolysis group and hemorrhagic transformation rate was33.3%(4/12);7presentedhemorrhagic transformation in the4h thrombolysis group and hemorrhagic transformation ratewas58.3%(7/12);5appeared without cerebral hemorrhage in the control group.Conclusions1.Streptozotocin and thromboembolism method could be used to successfullyprepare type2diabetes and be applied to cerebral infarction model with thrombolysis.2.rt-PA had a certain effect on type2diabetes rats with cerebral infarction. The neurologicaldeficits degrees of2h and3h thrombolysis group were lower compared with the cerebralinfarction rats waking up from anesthesia, but infarct volumes did not change significantly.3.The2h and3h thrombolysis group received more benefits and less risks than the4hthrombolysis group; Rats in2h and3h thrombolysis group presented lower neurologicaldeficits degrees, smaller volumes of cerebral infarction and lower hemorrhagic transformationrates than in the4h thrombolysis group. So the time windows should be strictly controlledduring thrombolytic therapy.