FIG. 1.

Urine nitrite excretion in response to C. trachomatis MoPn urogenital infection in disease-susceptible C3H/HeN mice and resistant C57BL/6 mice. Urine was collected daily from 6 days prior to infection until day 42 postinfection. Nitrite levels were assessed by the Greiss reaction and standardized according to urine creatinine concentration. The solid line represents the response for C57BL/6 mice. The dashed line represents that for C3H/HeN mice. Following clearance of dietary nitrates and nitrites (day −7 to day zero), a significantly higher level of excretion of nitrite was observed with C57BL/6 mice when the main effects of strain and time were compared (P = 0.0006; Kruskal-Wallis one-way ANOVA on ranks).