Abstract

BACKGROUND
Bacterial lipopolysaccharide (LPS), an endotoxin, can increase nitric oxide (NO) production by expression of an inducible isoforms of nitric oxide synthase (iNOS). Bacterial infections of the central nervous system dilate cerebral vessels and increase cerebral blood flow. We hypothesized that systemic and intraventricular application of bacterial lipopolysaccharide would increase cerebrospinal fluid (CSF) production due to increase in blood flow to choroid plexus caused by NO-induced vasodilation.
METHODS
Ventriculocisternal perfusion was used to measure the production of CSF in pentobarbital-anesthetized rats. The lateral ventricle and cisterna magna were cannulated stereotactically and perfused continuously with artificial CSF with blue dextran 2000 as the indicator. Baseline collections of CSF began after steady state outflow was established; then, endotoxin was administered intravenously or intraventricularly. The baseline rate of CSF production was compared with that measured during 3 hours after endotoxin administration.
RESULTS
The baseline rate of CSF production was 2.6 0.3 (2.2~3.5)microliter/minute in the rat. There were no significant changes in CSF production rate after intravenous or intraventriculr administration of endotoxin.
CONCLUSIONS
We could not observe significant changes in CSF production rate with the ventriculocisternal perfusion method of measuring CSF production after intravenous or intraventriculr administration of endotoxin in the rats.

• Keywords: Cerebrospinal fluid formation;Endotoxin;Ventriculocisternal perfusion;