Figure 1: Impactof ketotifen fumarate on incidence and severity of EAO score. All rats were immunized with testicular homogenate and adjuvants. A group of rats was injected with saline solution (vehicle) or ketotifen fumarate. (a) Treatment 1. Administration of ketotifen fumarate (4 mg kg−1) reduced the severity of orchitis. (b) Treatment 2. Similar EAO scores were observed in the two groups studied. Horizontal lines represent the mean. Each symbol represents a single rat. Values with different symbols superscript (#, &) differ significantly P < 0.05 (nonparametric one-way ANOVA Kruskal–Wallis test). (c) Testis section from vehicle group rats killed 56 days after the first immunization showing severe testicular damage characterized by germ cell sloughing of seminiferous tubules and interstitial inflammatory cell infiltrate. Note severe tubular atrophy showing decreased diameter of seminiferous tubules in vehicle rats. (d) In contrast, testis section from rats treated with ketotifen fumarate (4 mg kg−1) shows normal histological features. Scale bars = 100 μm. EAO: experimental autoimmune orchitis.