[Vascular endothelial growth factor expression in the rat dural arteriovenous fistula model].
Although various mechanisms of the development of dural arteriovenous fistula (DAVF) have been proposed, the pathogenesis of these lesions are still unclear. Recent experimental evidence suggested a role of angiogenic growth factors in the genesis of vascular malformations of the central nervous system. To further investigate the pathogenesis of DAVF, we examined the expression of the angiogenic growth factor, vascular endothelial growth factor (VEGF), in rat DAVF model.


METHODS
Male Wistar rats (weighting 280 to 300 g, n = 40) were used. Each rat was mounted on a stereotaxic frame under general anesthesia. DAVF model (Spetzler et al.) was made by common carotid artery-external jugular vein anastomosis, bipolar coagulation of the vein draining the transverse sinus, and superior sagittal sinus thrombosis (SSS). SSS was thrombosed by a hemostatic agent through 16-gauge needle. Venous hypertension was induced in 30 rats, which were divided into two experimental groups; (1) immunohistological study group (n = 15) and (2) angiography group (n = 15). Immunohistological analysis was performed by VEGF antibody 1 week after, and angiography was done 90 days after the surgery. Developing of angiographical DAVF was observed with the magnifying X-ray camera. Each 5 rats served as sham-operated controls, which received a similar surgery without induction of venous hypertension.


RESULTS
VEGF expression and DAVF were not observed in sham group. In immunohistological study group, VEGF expression in the endothelium and the connective tissues of the dura mater in the five rats (33%) and in the neurons in the eleven rats (73%) of the cerebral cortex and the basal ganglia were identified. In angiography group, DAVF formed in 6 among 15 rats (40%).


CONCLUSIONS
The findings of this study provide the first experimental evidence that angiogenic growth factors VEGF may participate in the genesis of DAVF. These results suggest a novel strategy for the management and prevention of DAVF and related disorders.
Shin
Yasushi
Y
Department of Neurosurgery, Nara Medical University, 840 Shijo-machi, Kashihara, Nara 634-8522, Japan.
Uranishi
Ryunosuke
R
Nakase
Hiroyuki
H
Sakaki
Toshisuke
T
D000818:Animals; D001479:Basal Ganglia / Q000378:metabolism; D020785:Central Nervous System Vascular Malformations / Q000209:etiology* / Q000378:metabolism*; D004195:Disease Models, Animal; D004388:Dura Mater / Q000378:metabolism; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D042442:Vascular Endothelial Growth Factors / Q000096:biosynthesis*; D014690:Venous Pressure / Q000502:physiology
D042442:Vascular Endothelial Growth Factors