Absolute bioavailability of ginkgolide compounds in rats / 中国中药杂志

To investigate the pharmacokinetic characteristics and absolute bioavailability of ginkgolide A (GA), ginkgolide B (GB) and bilobalide (BB) in rats. In this experiment, a high-performance liquid chromatography-tandem mass spectrometry (LC-MS/ MS) method was established to determine the plasma concentrations of GA, GB and BB in rats after rats were administrated with the three drugs through ig and iv respectively. The main pharmacokinetic parameters and absolute bioavailability of three ginkgolide compounds were obtained by using pharmacokinetic software DAS 2. 0. After the inject of GA, GB and BB, the results showed Cmax at (513.9 ± 116.9), (701.3 ± 76.0), (5,255.6 ± 476.8) µg · L(-1) and AUC0.24h of (960.9 ± 268.5), (779.5 ± 140.6), (7,409.3 ± 1,181.1) µg · h · L(-1), respectively; after the oral administration, the results showed Cmax at (522.9 ± 39.9), (146.8 ± 31.6), (2,711.9 ± 588.9) µg · L(-1) and AUC0-24 h of (1,760.4 ± 300.7), (636.6 ± 180.3), (16,651.4 ± 1,306.5) µg · h · L(-1), respectively. The absolute bioavailability of GA, GB and BB in rats was (61.1 ± 10.4)%, (27.2 ± 7.7)%, (56.2 ± 4.4)%, respectively. The method established in this experiment has a good specificity and sensitivity and so can be used to study the pharmacokinetics and absolute bioavailability of GA, GB and BB in rats.

Effect of Tianshu Capsule on neurotransmitter in rat model of dura mater following electrical stimulation / 中草药

Objective: To study the effect of Tianshu Capsule on the rat dura mater model of superior sagittal sinusin following electrical stimulation and discuss its mechanism. Methods: Male SD rats after brain electrode implantation were started on Tianshu Capsule at the doses of 1.08, 0.36, and 0.18 g/kg. Sumatriptanm Tablets at the dose of 9.72 mg/kg were ig given as a positive drug. Except control and Sham groups, the electrical stimulation was carried out in a voltage of 10 V, frequency of 3 Hz, pulse width of 0.25 ms, and time of 1 h. No operation was taken in the control group. The orbital blood was taken after 0, 30, and 60 min of the stimulation than taking brain tissue. The contents of calcitonin gene-related peptide (CGRP), substance P, and norepinephrine (NE) in plasma and brain tissue were detected by radio immunoassay. Results: Compared with the control group, there was no significant difference of CGRP, substance P, and NE contents in brain tissue of rats in the Sham group. Compared with the Sham group, CGRP in the brain tissue of rats in normal group was increased obviously, while substance P and NE levels were significantly decreased (P < 0.05). Comapred with the model group, the Tianshu Capsule could increase the content of NE in plasma and brain tissue (P < 0.05) while decrease CGRP level (P < 0.05). And Sumatriptanm Tablets could reduce the content of CGRP in plasma (P < 0.05). Conclusion: The Tianshu Capsule could significantly improve the damage of rat dura mater of superior sagittal sinusin following electrical stimulation by releasing neurotransmitter, which may be the mechanisms of migraine treatment.