实验性脑实质内注血后甲硫氨酸-脑啡肽的变化

Regional Brain Changes in Met-enkephalin in an Experimental Model of Intracerebral Hemorrhage

本实验采用脑内注入自体抗凝血造成实验性大鼠脑出血模型,然后,用放射免疫法对各脑区的甲硫氨酸-脑啡肽(MET-ENK)含量进行测定。结果:纹状体在注血后即刻比对照组有显著性下降(P<0.01);海马在注血后1小时比对照组有显著性下降(P<0.05);中脑在注血即刻及1小时均比对照组有显著性下降(P<0.05)。注血24小时后,上述各脑区MET-ENK含量均恢复至正常水平。并与注血后引起的偏瘫等神经学体征的恢复相平行。本实验提示脑申的MET-ENK参与脑出血后的生化反应,并可能与偏瘫等神经学体征的出现有关。

Regional brain changes in Met-enkephalin (MET-ENK) are described in an experimental model of intracerebral hemorrhage. Groups of rats received 10/μ1 of either autologous anticoagulated blood or saline stereotactically injected into the internal capsule. Animals were killed immediately after, 1 hour or 24 hours after the inoculation MET-ENK was measured by a sensitive and specific radioimmunoassay. In normal rats the highest concentrations of MET-ENK were found in the striatum (1100/mg) and the hypothalamus (800pg/mg). Immediately following intracerebral hemorrhage, MET-ENK concentrations were significantly reduced in the striatum and the midbrain. One hour after hemorrhage, MET-ENK was significantly reduced in the hipocampus and the midbrain. By 24 hours after hemorrhage, all brain regions returned to normal. In the saline injected rats, MET-ENK levels did not fall. Neurologic signs of contralateral hemiparesis, hyperventillation, rotational turning, and delirium or lethargy occured in most animalg following the intracerebral hemorrhage. Saline inoculated rats manifested only brief hyperventillation. All neurologic signs cleared by 12 to 24 hours. Histogic brain studies confirmed the blood inoculation in the internal capsule. This shudy demonstrates that a transient fall in METENK occurs on the striatum, hipocampus, and midbrain but not in the cerebral cortex or other brain regions following inoculation of autologous blood into the internal capsule. The transient fall in MET-ENK levls pralleled the neutologic stgns the neutologic signs that developed in the rats.