ABSTRACT
Objective To investigate the hyperglycemic effect on ultrastructural morphology and intercellular adhension molecule 1(ICAM 1) expression of BBB. Methods Hyperglycemia model was established by intravenous injection of streptozocin in SD rats. A dynamic observation on the changes of the ultrastructure and the ICAM 1 expression on endothelium of BBB in SD rats with hyperglycemia for 3 days to 8 months was carried out by transmission electron microscopy and immunohistochemical method. Results Swelling was slight in endothelium of BBB of rats with hyperglycemia for 3 days, became obvious and occurred in endfoot of astrocyte for 1 to 2 months, and some microthrombi appeared in cavity of capillary with various malformation and apoptosis was found in endothelium of BBB and neuron surrounding abnormal capillary for 3 to 8 months. With immunohistochemical study, ICAM 1 was expressed sparsely on endothelium of BBB in 3 days after injection of streptozocin, became markedly strong in 3 months, and progressed further in 6 to 8 months. There was no changes on BBB in both SD rats and negative controls. Conclusion Long term hyperglycemia could cause obvious ultrastructural changes of BBB, associated with ICAM 1 expression on endothelium of BBB induced by hyperglycemia