ABSTRACT
BACKGROUND: Dynamic balance of endothelin (ET) and calcitonin gene-related peptide (CGRP) plays an important role in occurrence and development of cerebral infarction.OBJECTIVE: To observe the effects of thromboiytic therapy with batroxobin(DF-521) on the levels of plasma ET and CGRP after cerebral infarction.DESIGN: Randomized controlled study.SETTING: Fourth Department of Gereology, General Hospital of Guangzhou Military Area Command of Chinese PLA.MATERIALS: The experiment was performed at the Fourth Department of Gereology, General Hospital of Guangzhou Military Area Command of Chinese PLA. Totally 15 New Zealand rabbits aged from 18-20 months, of common grade and either sex, with the mean body mass of (3.5±0.5) kg were selected.METHODS: A total of 15 rabbits were established into cerebral infarction models with modified autogeneic thrombus method. One rat died when selecting models. Other 14 rats were randomly assigned into control group and treatment group. DF-521 was slowly injected into vein of ear edge of rats in the treatment group at hour 2 after embolism. Saline of the same volume was slowly injected into rats of the control group. Changes of concentrations of plasma ET and CGRP in the treatment group and control group were observed before and after cerebral infarction.MAIN OUTCOME MEASURES: Changes of ET and CGRP contents 1 hour before operation, 2 hours after operation (before drug injection) and 6 hours after operation (4 hours after drug injection).RESULTS: Of the 15 included rabbits, 1 rat died when establishing model, so 14 rabbits were involved in the result analysis. ET level significantly increased at hour 2 after acute cerebral infarction operation in the treatment group and control group (P ＜ 0.05, P ＜ 0.01), and then decreased at hour 6 after operation (P ＜ 0.01 ,P ＜ 0.01 ). The decrease in the treatment group was larger than that in the control group (P ＜ 0.01 ). The level of CGRP markedly reduced at hour 2 after acute cerebral infarction operation in the two groups, and than increased at hour 6 after operation. The increase in the treatment group was larger than that in the control group, but there was no statistical difference (P ＞ 0.05).CONCLUSION: Body with cerebral infarction during acute stage has selfregulative mechanism on dysequilibrium of ET and CGRP. Early-used thrombolytic therapy with DF-521 can markedly increase the ET level,which may be one of the protective mechanisms of cerebral ischemical reperfusion injury.
ABSTRACT
AIM:To explore the protective effect of ischemic preconditioning on myocardial capillary bed. METHODS: Anesthetized open-chest dogs in ischemic preconditioning (IP) group ( n =6) were subjected to 5 min ischemia and 5 min reperfusion for 4 times in left descending coronary artery (LDA) while the dogs in sham-operated (SO) group ( n =6) were observed for 40 min without any stimulating. Myocardial contrast echocardiography (MCE) was performed before the surgery, at the end of the first and the fourth ischemia and reperfusion period, respectively. Myocardial samples in ischemic area were obtained for capillaries ultrastructure examination and their quantitative analysis was conducted by corresponding imagine analyzing system, then compared within group and between control group. RESULTS: (1) Comparing fourth 5 min ischemia with first one, the percents of area defect in minimum (AD min%) by MCE decreased from 32.6%?5.7% to 21.8%?5.2%( P