Figure 9.
Effect of ondansetron on apoptosis in the intestinal crypt and up-regulation of cytokine mRNA in the intestine induced by 5-FU in mice. Animals were injected with 5-FU (50 mg·kg−1, i.p.) and killed 1 day (24 h) later. Ondansetron (OND, 5 mg·kg−1) was administered p.o. twice 0.5 h before and 8 h after the administration of 5-FU. Apoptosis was assessed using the TUNEL assay (A, 500×). The number of TUNEL-positive cells was counted in the intestinal crypt using a light microscope (B). The expression of TNF-α, IL-1β, IL-6 and IFN-γ was quantified by real-time RT-PCR (C). Expression levels of each mRNA were standardized to that of β-actin mRNA and normalized to the mean value for normal (5-FU-untreated) mice. Data are presented as the means ± SEM from six mice. Significant differences at P < 0.05; *from control (C, vehicle alone); #from normal (N, 5-FU-untreated).