[The neuroprotective effects and its mechanisms of qingkailing injection on bacterial meningitis induced by E. coli in rabbits].

Objective: To explore the neuro-protective effect and mechanism of qingkailing injection (QKL) against cerebral injury caused by E. coli-meningitis (CM).

Methods: The CM model rabbits were treated by ampicillin with QKL as adjuvant. The leukocyte count and protein content in cerebral spinal fluid (CSF), the contents of water, sodium, potassium and calcium in cerebral tissues were measured before, 16 h and 26 h after Bacillus coli injection respectively. The expression of matrix metalloproteinase-9 (MMP-9) was determined at the same time.

Results: Adjunctive treatment with QKL can not only inhibit the increase of leukocyte cells, protein content in CSF, and water, sodium, calcium content in cerebral tissues, but also the decrease of potassium content revealed during simple antibiotic treatment. It also can decrease the expression of MMP-9 in cerebral tissues of rabbits with CM.

Conclusion: As an adjunctive treatment, QKL can prevent transient inflammatory reaction and aggravation of brain injury in CM induced by simple antibiotic treatment, its mechanisms might relate with calcium antagonism and attenuation of MMP-9 expression in brain tissues.