The Effects of Intraventricular Injection of Lipopolysaccharide on the Periventricular Neural Tissue

ABSTRACT

Ventriculitis is one of the most serious complication of the ventriculoperitoneal shunt, which may cause intelligence deterioration in children. The purpose of this study is to investigate the mechanism of the neural damage in lipopolysacciride(LPS)-induced ventriculitis in rat. Ventriculitis was induced by intraventricular injection of 1mg/Kg LPS in rat. H & E and Tunel stains were done on the day 1, 2 and 14 to access the microscopic changes of the periventricular tissue and apoptosis, respectively. TNF-alpha and IL-1beta mRNA expressions were studied using RT-PCR. HRP was injected into the femoral vein and electron microscopic examinations were performed to access the BBB changes. Light microscopic examination one day after LPS injection revealed neutrophilic infiltration, which diminished on day 4, and disappeared on 14. Tunel stain revealed apoptosis on day 1 and 4. TNF-alpha and IL-1beta were expressed on day 1, and diminished progressively thereafter. HRP histochemical electron microscopic examination revealed accumulation of HRP reaction in the interstitial space around the brain parenchyma. These findings suggest the opening of the BBB and increased capillary permeability in the periventricular tissue in the LPS induced ventriculitis. This can possibly damage the periventricular neural tissue. TNF-alpha and IL-1beta seemed to play an important role in the opening of the BBB.