Progresses of pericytes in central nervous system microvascular diseases / 国际儿科学杂志

Pericyte is a type of important cellular constituents in the central nervous system (CNS),which is located at periphery of the microvessel wall,surrounded by basement membrane (BM) and connected with endothelial cell (EC) and astrocytes endfeet.As such important components of microvasculature,diverse functions have been assigned to pericytes,including control of brain blood flow,development and maintenance of the blood-brain barrier,regulation of the neuroinflammation and may function as pluripotent stem cells.The dysfunction of brain pericytes is associated with the progression of many CNS diseases.The occurrence of the disease leads to pericytes injury.The dysfunction of the brain pericytes make the disease worse.Increasing evidence suggests a highly specialized role for pericytes in a wide range of CNS diseases like Alzheimer's disease,stroke,subarachnoid hemorrhage,epilepsy and so on.

Brain microvascular basement membrane damage and the expression of uPA and uPA mRNA in brain areas after focal cerebral ischemia/reperfusion in renovascular hypertensive stroke-prone rats / 中国病理生理杂志

AIM: To explore the structural changes of brain microvasculature and mechanism in microvascular lesion after focal cerebral ischemia with reperfusion. METHODS: Using the techniques of immunohistochemical staining, in situ hybridization,optical microscopy and transmission electron microscopy, the expression of uPA, uPA mRNA, and changes in miocrovascular structure were examined in ischemic focus and perifocal areas after focal cerebral ischemia 2 hours with various time points of reperfusion in stroke-prone renovascular hypertensive rats (RHRSP). RESULTS: The brain edema and hemorrhage were severe 12 hours to 3 days after reperfusion. Ultrastructural change showed that the damage characterizations of the basement membrane were degradation, defection, and exfoliated of basement membrane, while uPA, which attack the basememt membrane around cerebral capillaries and extra-cellular matrix, and uPA mRNA expression increased significantly in ischemic and perifocal areas 12 hour to 3 day after reperfusion. CONCLUSION: The main pathologic mechanism of brain edema and hemorrhage after cerebral ischemia with reperfusion may result from the basement membrane lesion of brain microvasculature. The increase in the expression of uPA in reperfusion area may be the main cause of the basement membrane lesion .