The effect of the acetaminophen treatment on liver function and cytokine gene expression. (A) Acetaminophen was administered to male HA mice by an intraperitoneal injection. At each time interval, the serum ALT level was estimated. Control mice “C” received normal saline (n = 6 for each group). *P < .001. (B) RT-PCR analysis of different growth factor transcripts. Acetaminophen was administered to several mice, and they were killed at 12, 24, and 48 hours. The control mice received saline. A representative gel picture shows the induction of growth factor transcripts in damaged liver tissue.