The Expression Of Endothelin-1 On Cerebral Artery In Rats After Subarachnoid Hemorrhage

objective To order to explore the relationship between endothelin-1 (ET-1) nerve fibers on cerebral artery, the level of ET-1 in plasma, the expression of ET-1 mRNA on basilar artery in rats and subarachnoid hemorrhage(SAH) induced cerebral vasospasm(CVS), and to offer morphological data for probing pathogenesis of SAH-induced CVS. Methods 144 Wistar rats were randomly divided into normal, experimental groups, sham-operated, and then the experimental groups were subdivided into SAH 2,3,7 and 14 day group. SAH was induced by immediate injection of autologous arterial blood which was freshly withdrewn from femoral artery, into the subarachoid. The density of ET-1 nerve fibers on the cerebral artery,the level of ET-1 in plasma and the alteration of Endothelin-1 mRNA level of on basilar artery in rats were measured with immunohistochemical ABC method,radioimmunoassay(RIA) technique and reverse transcription polymerase chain reaction(RT-PCR), respectively, during subarachnoid hemorrhage-induced cerebral vasospasm. Results The ET-1 immunoreactive postive fibers, brown liner structures, were observed on anterior cerebral artery,middle cerebral artery,posterior cerebral artery and basilar artery, The density of ET-1 nerve fibers on cerebral arteries of 2d,3d group after SAH was higher than that of normal group, especially the of 3 group after SAH. The level of ET-1 in plasma of 2,3,7 group after SAH were higher than that of normal group(p<0.005), at 14 group after SAH, the level of ET-1 recovered to normal (p>0.05). The expression of ET-1 mRNA on basilar artery 2,3 and 7 group in SAH was obviously higher than that of normal group, while that of 14 group was approximate to normal group. Conclusion The increase of ET-1 nerve fibers density on cerebral artery in SAH rats, the enhancement of ET-1 level in plasma and the rise of ET-1 mRNA expression on basilar artery in SAH rats, which shows that ET-1 participate in pathophysiological process of SAH-induced cerebral vasospasm, and it suggests that ET-1 play an important role in SAH-induced cerebral vasospasm .