ABSTRACT
Objective To investigate the expressions of aquaporin 4 (AQP4) in the bacterial meningitis in rats and to explore the molecular mechanism for brain edema caused by bacterial meningitis.Methods Totally 40 of 3-week-old-Sprague-Dawley healthy rats,body weight 60-80 g,male or female,were divided into a normal control group(n =10),and infection groups:24 hours after injection(n =10),48 hours after injection(n =10),and 5 days after injection(n =10).The expressions of AQP4 in the brain were detected by immunohistochemistry and Western blot methods respectively after 24 hours,48 hours,5 days of inoculation.Results Mortality rate:no rats in the control group and the infection group after 24 hours were dead.Two rats in the infection group after 48 hours and 4 rats in the infection group after 5 days were dead because of serious sickness,with the mortality rates 20％ and 40％,respectively.AQP4 expression was slightly positive under light microscope,and the positive cells mainly surrounded glial cells and blood vessels,while neurons were not dyed.Immunohistochemical staining showed that AQP4 expression in the model group increased with the severity of edema;compared with the control group,the AQP4 expression in the brain tissues increased in different periods after rats were infected,and the differences between groups were statistically significant (F--91.84,P ＜ 0.01).Western blot analysis showed that after the brain received streptococcus pneumoniae injection,expression of AQP4 began to increase in 24 hours after streptococcal injection,and reached to the peak in 48 hours,but decreased in 5 days,but the expression still remained higher than that of the normal control group.Each group had statistically significant difference(F =14.23,P ＜ 0.01).Conclusions Expression of AQP4 in the models with bacterial meningitis may increase initially and decrease later.It suggests that AQP4 plays a protective role during the development of infectious brain edema.
ABSTRACT
The quality control of traditional Chinese medicine (TCM) preparations is a key issue related to their curative effect, safety and stability. The application of modern analytical means and the development of new disciplines improve the quality control of TCM preparations to some extent. For a long time, however, the quality control level of TCM preparations remains low and the quality standards exist in name only unable to effectively control drug quality and ensure therapeutic effect and safety. The essay makes a systematic analysis on possible factors impacting TCM preparations and current situation of quality control and discusses possible approaches and new methods for improving quality control of TCM preparations, in order to give an impetus to the quality control standards and the mode evolvement of TCM preparations and ensure safety, efficiency and quality controllability of TCM preparations.