Study on pharmacokinetics and in vitro/in vivo correlation of menthol in Zhike Chuanbei Pipa dropping pills in rats / 中国中药杂志

To determine the concentration of menthol in rat plasma by GC. Rats were administered with single dose of Zhike Chuanbei Pipa dropping pills (ZCPDP) and different doses of menthol herbs. DAS 3. 1.6 software was used to calculate pharmacokinetic parameters, and the accumulative absorption percentage of menthol was calculated by Loo-Riegelman method. The linear regression analysis was made in vitro/in vivo accumulative absorption percentages to detect the in vitro/in vivo correlation. The results of the study showed that the pharmacokinetics behavior of menthol in ZCPDP was in conformity with two-compartment model characteristics. The main parameters were: tmax was 10 min, t1/2beta was (183. 93 52. 75) min, CL/F was (0. 426 +/- 0. 194) L . min-1 . kg-1, all of which were no difference between ZCPDP and menthol herbs with the same dosage. There were significant differences in tmax, t1/2beta, CL/F between menthol herbs with different dosages (P <0. 05) , with indirect proportion between AUC0-infinity and dosage. The regression equation of ZCPDP's accumulative absorption percentage and accumulative release percentage was Fa = 1. 160 3Q - 19. 968, r = 0. 981 3. These results suggested that the pharmacokinetics behavior was similar between ZCPDP and menthol herbs with the same dosage in rats, with good in vitro/in vivo correlation. There were significant differences in pharmacokinetics of menthol in the range of 19.2-570 mg . kg-1.

In vitro studies on the growth and proliferation characteristics of rat bone mesenchymal stem cells / 中华预防医学杂志

<p><b>OBJECTIVE</b>This study was to investigate the growth and proliferation characteristics of rat bone mesenchymal stem cells (BMSCs) isolated by the method of whole bone marrow culture and to explore the effect of cell inoculation density and incubation period on cell proliferation, with an aim to provide multipotential seed cells for preventing from degenerative disease.</p><p><b>METHODS</b>Bone mesenchymal stem cells were isolated by the method of whole bone marrow culture and then cultured in vitro. The cell morphologic features were observed by inverted microscope. The cell surface antigens were identified by flow cytometry. The effect of cell inoculation density and culture period on cell growth and proliferation was explored by analyzing the characteristics of a ten-day cell growth curve in 96-well plates.</p><p><b>RESULTS</b>Flow cytometry results showed the detection rates for CD29, CD34 and CD45 were 97.68% (7607/7788), 7.93% (661/8340) and 2.76% (215/7788) respectively, which was consistent with the expression characteristics of BMSCs surface antigens. BMSCs became uniform after three cell passages, existing in a typical shape of whirlpool or radial colony. The senescent cells started to appear at 7(th) passage, and more senescent cells were found at 10(th) passage. The growth curve for moderate inoculation density was typically S-shaped. Lag phase was found during the first two days, and logarithm growth phase was in the following three days. Plateau phase started from the 6(th) day and cell numbers decreased slightly from the 8(th) day.</p><p><b>CONCLUSION</b>The whole bone marrow culture is an effective way to obtain BMSCs. A moderate inoculation density was more advantageous to cell proliferation, by which more seed cells could be obtained.</p>