OBJECTIVETo study the possible mechanism of protective effect for Baicalin on Bacillus pertussis (BP) infected brain tissue and the dose-effect relationship.

METHODSBrain tissues slices were divided into 7 groups: (1) the normal group; (2) the model group: infected by 10% BP; (3) the baicalin group, which was pretreated with baicalin, infected by BP and subdivided into 5 sub-groups according to different doses of baicalin used; (4) the glutamic acid group: cultured with glutamic acid; (5) the baicalin plus glutamic acid group; (6) the peroxide group: cultured with hydrogen peroxide; and (7) the baicalin plus peroxide group. The lactate dehydrogenase (LDH) content in the supernatant of culture was determined and quantitative protein determination was conducted.

RESULTSThe LDH releasing was higher in the model group, glutamic acid group and peroxide group as compared with that in the normal group, 15.10 +/- 4.89 u/g. protein (the same unit below), 15.49 +/- 5.66 and 16.54 +/- 5.47 vs 6.10 +/- 2.87 respectively (P < 0.01). After being pretreated with 0.25 mmol/L baicalin, LDH level decreased significantly to 8.65 +/- 2.43, which was significantly different from that in the model group (P < 0.01), LDH was also decreased in the baicalin plus glutamic acid group (9.93 +/- 2.89) and baicalin plus peroxide group (9.54 +/- 2.82), which was significantly lower than that in the glutamic acid group and the peroxide group respectively (P < 0.01).

CONCLUSIONPretreatment of baicalin has protective effect on BP caused nerve cell injury in rat brain slices, the protection is possibly related with the reduction of glutamic acid and hydrogen peroxide induced damage on nerve cells in vitro.