Measurements in samples of cerebrospinal fluid. (A) White blood cell count in cerebrospinal fluid samples obtained 18 h after infection (hours post infection (hpi)). No effect after pre-treatment with the MMP inhibitor (RS) was observed when compared to vehicle treated littermates (control (Ctrl)). Leukocyte counts were reduced after treatment with RS in the survivors of the disease (P < 0.05, Mann-Whitney test; squares). (B) Total collagen content was quantified at 18 and 27 hpi (optical density at 550 nm [OD550] was used as arbitrary unit). Concentrations were lower in animals treated with RS compared to control littermates, although this effect did not reach statistical significance (P = ns).