Seiichiro Nishida1, Hiroyasu Satoh. 1. Department of Pharmacology, Division of Crude and Herbal Medicine, Nara Medical University, Kashihara, Nara 634-8521, Japan.
Abstract
BACKGROUND: Comparative vasodilating actions of the constituents of Ginkgo biloba extract (GBE), terpenoids (bilobalide, ginkgolides A, B and C) and flavonoids (quercetin and rutin), were examined using rat aorta ring strips. METHODS: Cumulative administrations of GBE and its constituents were followed with the pretreatment of 5 micromol/l NE. RESULTS: GBE at 0.03 to 3 mg/ml had a potent concentration-dependent relaxation; by 70 +/- 4.5% (n = 6, P < 0.001) at 3 mg/ml. Terpenoids and flavonoids at 0.1 to 100 micromol/l had potent concentration-dependent relaxation. At 100 micromol/l, bilobalide dilated by 17.6 +/- 3.9% (n = 7, P < 0.05), and ginkgolides A, B and C also caused it to the almost same extent. Quercetin (100 micromol/l) caused a potent vasorelaxation by 49.9 +/- 4.8% (n = 10, P < 0.001). Rutin at 100 micromol/l had weaker vasorelaxation; by 13.7 +/- 3.2% (n = 6, P < 0.01). CONCLUSIONS: All constituents of GBE have the concentration-dependent vasorelaxtant effect. The potency of GBE's action was not made simply by addition of those of the constituents. Each constituent itself would contribute to the GBE-induced vasodilation, although the constituents have the complicated interactions with each other.
BACKGROUND: Comparative vasodilating actions of the constituents of Ginkgo biloba extract (GBE), terpenoids (bilobalide, ginkgolides A, B and C) and flavonoids (quercetin and rutin), were examined using rat aorta ring strips. METHODS: Cumulative administrations of GBE and its constituents were followed with the pretreatment of 5 micromol/l NE. RESULTS: GBE at 0.03 to 3 mg/ml had a potent concentration-dependent relaxation; by 70 +/- 4.5% (n = 6, P < 0.001) at 3 mg/ml. Terpenoids and flavonoids at 0.1 to 100 micromol/l had potent concentration-dependent relaxation. At 100 micromol/l, bilobalide dilated by 17.6 +/- 3.9% (n = 7, P < 0.05), and ginkgolides A, B and C also caused it to the almost same extent. Quercetin (100 micromol/l) caused a potent vasorelaxation by 49.9 +/- 4.8% (n = 10, P < 0.001). Rutin at 100 micromol/l had weaker vasorelaxation; by 13.7 +/- 3.2% (n = 6, P < 0.01). CONCLUSIONS: All constituents of GBE have the concentration-dependent vasorelaxtant effect. The potency of GBE's action was not made simply by addition of those of the constituents. Each constituent itself would contribute to the GBE-induced vasodilation, although the constituents have the complicated interactions with each other.
Authors: Sarah M Weakley; Xinwen Wang; Hong Mu; Jianming Lü; Peter H Lin; Qizhi Yao; Changyi Chen Journal: J Surg Res Date: 2011-04-01 Impact factor: 2.192
Authors: Mary Akinyi; Xiu Mei Gao; Yu Hong Li; Bing Yao Wang; Er Wei Liu; Li Juan Chai; Abdulai JawoBah; Guan Wei Fan Journal: Int J Clin Exp Med Date: 2014-10-15