Development and application of high-performance liquid chromatography for the study of ampelopsin pharmacokinetics in rat plasma using cloud-point extraction.

A simple, rapid and specific method based on cloud-point extraction (CPE) was developed to determine ampelopsin in rat plasma after oral administration by reversed-phase high-performance liquid chromatography. The non-ionic surfactant Genapol X-080 was chosen as the extract solvent. Some important parameters affecting the CPE efficiency, such as the nature and concentration of surfactant, extraction temperature and time, centrifuge time and salt effect, were investigated and optimized. Separation was accomplished using a C(18) column by gradient elution with a acetonitrile-phosphate buffer solution as the mobile phase. The detection wavelength was set at 290 nm. Under optimum conditions, the linear range of ampelopsin in rat plasma was 20-2000 ng/mL (r(2)=0.9996). The limit of detection was 6 ng/mL (S/N=3) with the limit of quantification being 20 ng/mL (S/N=10). The proposed method has been successfully applied for pharmacokinetic studies of ampelopsin from rat plasma after oral administration.

[Protective effect of Sankang Capsule on immunity-deficiency mice induced by cyclophosphamide].

OBJECTIVE: To study the immunomodulatory effect of Sankang Capsule( SKC) on the immunity-deficiency mice. METHODS: The immunity-deficiency model was induced by intraperitoneal injection (ip) of cyclophosphamide (CTX) at the dose of 100 mg/ kg in mice which were randomly divided into normal control group, immunity-deficiency model group, SKC treated group (250 mg/kg, 500 mg/kg) and positive control group (500 mg/kg). The number of WBC in peripheral blood, the weight of immune organs, the phagocytosis activity of macrophage, the content of serum hemolysin and the proliferation of T lymphocyte in the spleen were measured. RESULTS: The number of WBC, the weight of immune organs, the phagocytosis activity of macrophage, the content of serum hemolysin and the proliferation of T lymphocyte in the model group were all decreased compared with those of normal control group. After the administration of SKC, the index mentioned above was increased compared with those of model group. CONCLUSION: SKC has a protective effect on the immunity-deficiency mice, which may be related to the increasing of cellular immunity, humoral immunity and nonspecific immunity.

Effect of sinomenine on morphine dependence in isolated guinea pig ileum.

OBJECTIVE: To investigate the effects of sinomenine on morphine withdrawal response and acetylchline (Ach)-induced contracture in isolated guinea pig ileum. METHODS: The withdrawal contracture was elicited by subjecting isolated ileum incubated with morphine (3 micromol/L) at 37.5 degrees Celsius for 4 h to naloxone (1 micromol/L) treatment. Sinomenine (10, 50, 250 micromol/L) and nimodipine (Nim, 0.1 micromol/L) were administered 1 min before and after naloxone in morphine-dependent ilea bathed in Krebs solution containing morphine, to observe the changes in the withdrawal contracture of the ileum. The effect of sinomenine (10, 50, 250 micromol/L) on the contracture of untreated ileum in Krebs solution elicited by acetylcholine was also observed. RESULTS AND CONCLUSION: Naloxone-induced withdrawal contracture or acetylcholine-induced contracture of the ileum was significantly decreased in a dose-dependent manner, indicating that sinomenine can inhibit morphine withdrawal symptoms in guinea pigs.