Cytokines mediate many of the pathophysiologic responses in gram negative bacteremia and meningitis, but it is unclear about the kinetics of endogenous cytokines in vivo. For this reason this study was undertaken using 5-day-old Sprague Dawley
rat
pups
infected subcutaneously with hib Paired serum and cerebrospinal fluid(CSF0 were collected before and 18, 42, 66, and 90 hrs after Hib inoculation for determination of cytokine concentration (TNF-a and IL-6), bacterial colony counts(CFUs), and
white
blood cell(WBC) counts, TNF-f was measured by the WEHI cytotoxicity assay and IL-6 was measured by B9 proliferation assay.
Serum and CSF CFUs were highest 18 and 42 hrs after inoculation, respectively. Mean CSF WBC count was highest after 66 hrs. Serum TNF-a levels peaked at hrs(mean±SD ; 31.54±15.84 ng/ml), while CSF TNF-a levels peaked at 42 hrs(mean±SD ;
64.67±60.38
ng/ml). TNF-a levels correlated with the log of CFUs and WBC counts in CSF(p<0.05). Both serum and CSF IL-6 levels peaked at 42 hrs(mean±SD ; 37987.14±40931.65 pg/ml, 245728.6±2548668.0 pg/ml).
Interleukin 6 levels correlated with the log of CFUs in CSF(p<0.05), but there was no correlation between Il-6 and log of CFUs in serum.
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