天麻素在大鼠脑、肝、肾及脑不同区域组织匀浆中的代谢研究

Study on the Metabolism of Gastrodin in Rat Brain, Liver, Kidney and Different Brain Regions Homogenate

关键词:  天麻素  天麻苷元  对羟基苯甲醇  匀浆  体外代谢  脑

Key words:  gastrodin  gastrodigenin  p-hydroxybenzyl alcohol  homogenate  metabolism in vitro  brain

摘要:

目的研究天麻素在大鼠脑、肝、肾和脑不同区域组织匀浆中的代谢。方法采用体外匀浆孵育，高效液相法测定天麻素代谢物。结果在脑、肝、肾匀浆中，天麻素代谢物苷元(对羟基苯甲醇)的生成反应速度常数分别为0.030 5，0.012 1，0.140 9 μg·mL-1·min-1，天麻素在大鼠脑、肝和肾匀浆中的清除率分别为(29.7 ± 2.1)，(10.4 ± 0.8)和(299.5 ± 22.7)μL·min-1·g-1。天麻素在脑、肝匀浆中代谢较慢，在肾匀浆中能被迅速代谢。在脑组织不同区域中，天麻素被代谢生成苷元的反应速度常数以小脑、脑桥与延脑、丘脑3个区比较高，皮层、纹状体、海马3个区比较低，前者为后者的约1.5倍。天麻素在大鼠小脑、丘脑、皮层中的清除率分别为(45.9 ± 7.4)，(39.6 ± 5.6)和(24.4 ± 3.0)μL·min-1·g-1。结论天麻素在非酶体系中稳定，在肝、肾、脑组织匀浆中天麻素可被代谢为天麻苷元。在组织中的代谢，以肾最快，脑次之，肝最小；在脑组织中，天麻素在小脑、丘脑、脑桥与延脑区域代谢速度快于皮层、纹状体和海马区。

Abstract:

OBJECTIVE To study the metabolism of gastrodin (Gas) in rat brain, liver, kidney and different brain regions. METHODS Gas was incubated in different tissue homogenate at 37℃ in vitro. An HPLC method was established to determine the metabolite concentration after incubation. RESULTS The results showed the velocity constants of formation metabolite, HBA, were 0.030 5, 0.012 1 and 0.140 9 g·mL-1 min-1 in brain, liver and kidney, respectively. The clearance rates of Gas were (29.7 2.1), (10.4 0.8) and (299.5 22.7) L·min-1·g-1 in the brain, liver and kidney, respectively. The metabolism rate of Gas was slow in brain and liver, while it was fast in kidney. In brain homogenate, the formation velocity of HBA was fast in the cerebellum, thalamus, pons and medulla oblongata, and slow in the frontal cortex, hippocampus and striatum. The velocity constants of the formers were about 1.5 times higher than those of the latters. Clearance rates of Gas were (45.9 7.4), (39.6 5.6) and (24.4 3.0) L·min-1·g-1in cerebellum, thalamus and cortex, respectively. CONCLUSION Gas is stable in non-enzyme system and can be metabolized to HBA in brain, liver and kidney homogenate in vitro. And Gas is metabolized most rapidly in the kidney. The metabolism rates of Gas in the cerebellum, thalamus, pons and medulla oblongata are faster than other three brain regions.