The Effects of Hyperhomocysteinemia on the Ultrastructures of Cerebral Microvessels / 대한해부학회지

ABSTRACT

Elevated plasma level of the sulfur amino acid homocysteine, termed hyperhomocysteinemia, is now recognized as a contributing factor to various pathological states of the brain including vascular, degenerative and other neurologic disorders. Endothelial dysfunction may be one of the underlying mechanisms leading to proatherogenic and neurotoxic effects associated hyperhomocysteinemia. We conducted electron microscopic studies to investigate microvascular changes in hyperhomocysteinemic rat brain due to folate deficiency. Dietary folate deprivation caused an increase in plasma Hcy by 317% from 6.15 +/- 0.9 micro mol/l to 19.5 +/- 3.2 micro mol/l with time up to 8 weeks of folate deprivation. In electron microscopic study, perivascular amorphous fibrosis, and pericytic and endothelial cell degenerative appearance were frequently found in hyperhomocysteinemic microvasculature. These findings are very similar with the typical cerebral microvascular pathology observed in neurodegenerative and aging processes. From these results, it can be suggested that hyperhomocysteinemia -induced blood -brain barrier disruption give rise to subsequent neuronal dysfunction in hyperhomocysteinemia.