Effects of extract of Ginkgo biloba on spasms of the basilar artery and cerebral microcirculatory perfusion in rats with subarachnoid hemorrhage.
This study was aimed at investigating the effects of extract of Ginkgo biloba (EGb) on cerebral vasospasm and microcirculatory perfusion after subarachnoid hemorrhage (SAH). An endovascular piercing method was used to induce Wistar rat SAH models, and animals were divided into sham-operated, vehicle controls, and EGb-treated groups. EGb was injected intraperitoneally 30 minutes before operation and was repeated every 6 hours, with a single dose of 15 mg/kg bw. Diameters of basilar arteries before and after operation were measured. Microcirculatory blood perfusion of parietal lobe cortex was detected using a laser Doppler flow-meter probe within 24 hours. Endothelin-1 levels in both plasma and brain tissue were detected at different time points. The results showed that SAH caused an immediate drop in microcirculatory blood flow in vehicle controls, which persisted for 24 hours. Endothelin-1 levels in both plasma and brain tissue increased after SAH. EGb partly reversed spasms of the basilar artery and antagonized a drop in microcirculatory blood flow. EGb also prevented an increase in endothelin-1 both in plasma and in brain tissue. In conclusion, EGb, by antagonizing the overproduction of endo- thelin-1, partly reverses cerebral vasospasm and improves microcirculation, and thus relieves secondary ischemic brain injury after experimental SAH.
Sun
Bao-Liang
BL
Institute of Microcirculation, Affiliated Hospital of Taishan Medical College, Taian, Shandong 271000, China. blsun88@hotmail.com
Zhang
Jian
J
Wang
Xing-Cheng
XC
Xia
Zuo-Li
ZL
Yang
Ming-Feng
MF
Zhang
Su-Ming
SM
Ye
Wen-Jing
WJ
Yuan
Hui
H
D000818:Animals; D001488:Basilar Artery / Q000187:drug effects*; D002545:Brain Ischemia / Q000209:etiology / Q000517:prevention & control; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D004353:Drug Evaluation, Preclinical; D019332:Endothelin-1 / Q000096:biosynthesis / Q000097:blood / Q000235:genetics; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D020441:Ginkgo biloba / Q000737:chemistry*; D007274:Injections, Intraperitoneal; D008297:Male; D008833:Microcirculation / Q000187:drug effects; D023421:Models, Animal; D010296:Parietal Lobe / Q000098:blood supply / Q000187:drug effects; D008517:Phytotherapy; D010936:Plant Extracts / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D010946:Plants, Medicinal / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D013345:Subarachnoid Hemorrhage / Q000150:complications*; D014661:Vasoconstriction / Q000187:drug effects; D014665:Vasodilator Agents / Q000008:administration & dosage / Q000494:pharmacology / Q000627:therapeutic use*; D020301:Vasospasm, Intracranial / Q000188:drug therapy*
D019332:Endothelin-1; D010936:Plant Extracts; D014665:Vasodilator Agents