ABSTRACT
Aim To study and compare the pharmaco-kinetic parameters of roxithromycin under normoxic and hypoxic rats. Methods A highly effective and rapid ultra-performance liquid chromatography with tandem mass spectrometry ( UPLC-MS/MS) method with posi-tive electrospray ionization source was successfully de-veloped and validated for quantification of roxithromy-cin in rat plasma. Sprague-Dawley rats were randomly divided into the hypoxia and normoxic groups. Each rat obtained a single dose of roxithromycin with 10 mg · kg-1 via intragastric administration. The pharmacoki-netic parameter comparison between normoxic and hy-poxic groups was calculated by SPSS software using in-dependent sample t test method. Results The main pharmacokinetic parameters of roxithromycin between the normoxic and hypoxic rats were:the AUC(0-t) 7 576 and 3 761 μg·h·L-1 , MRT(0-t) 5. 6 and 7. 7 h, T1/2 3. 4 h and 3. 9 h, CL 1. 5 and 3. 0 L · h-1 · kg-2 , tmax3. 1 and 3. 4 h, Cmax 1 116 and 372 μg·L-1 , re-spectively. The levels of Cmax and AUC of roxithromy-cin in hypoxic rats were statistically lower than those in normoxic rats. Conclusion The exposure level of rox-ithromycin in hypoxic rats markedly decreased. Our re-sults may provide an important experimental basis to adjust the dosage for roxithromycin in hypoxic clinical practice.
ABSTRACT
Objective To develop and fully validate an UPLC-MS/MS method for simultaneous quantification of six active in?gredients in Rhodiola extract including salidroside,rhodiosin,rhodionin,herbacetin,kaempferol and quercetin. Methods The chro?matographic separation of the analytes was achieved by using Zorbax Eclipse plus C18 column(2.1 mm×100 mm,3.5μm). The mobile phase consisted of 0.2%aqueous formic acid and acetonitrile. Analytes were separated using a linear gradient with a flow rate of 0.4 ml/min. The column temperature was set at 25℃. The mass spectrometric conditions were electrospray negative ionization(ESI)and the scan?ning mode was multi reaction monitoring(MRM). Results The calibration curves of the six active ingredients were linear over 10-20000,10-4000,10-4000,5-2000,10-2000,and 5-2000 ng/ml concentration ranges,respectively. The RSD of the instrument precision was within 3.31%. The current assay was stable and reproducible in quantification of all analytes with RSD within 5.07%and 4.05%,respectively. The average recovery of all analytes was in a range from 99.27%to 108.91%,with an acceptable RSD of no more than 4.92%. Conclusion The UPLC-MS/MS method could be successfully applied to simultaneously quantifying six major active in?gredients in Rhodiola extract with the acceptable specificity,sensitivity and reproducibility.
ABSTRACT
AIM: To study the protect effects of paecilomyceps sinensis sp nov (CN-802) on immunological liver injury in mice which induced by BCG+LPS. METHODS: LPS was injected into mice via the tail vein pretreated with BCG. The activity of serum ALT, the weighing indexes of liver and spleen, the levels of LPO in serum and hepatic tissues, and the numbers of subgroup of T lymphocyte were determined respectively. RESULTS: CN-802 at dose of 1.0 g?kg -1?d -1 decreased the serum ALT level, the liver and spleen-enlarged index and the LPO levels in serum and hepatic tissues. Analysis of CD_4/CD_8 in the peripheral blood showed that CN-802 increased the number of CD_4 lymphocyte and the ratio of CD_4/CD_8. CONCLUTION: Pretreatment with CN-802 prevents the immunological liver injury induced by BCG+LPG, and the effect of CN802 may be related with the regulatory of immune cells.