Protective effect of dantrolene sodium on carbon tetrachloride induced liver injury in the rat.

The effect of dantrolene sodium on liver injury induced by CCl4 was investigated in the rat. Liver microsomal P-450 and b5 levels, serum triiodothyronine levels (T3), and alanine aminotransferase activity (ALT) were measured over 4 to 16 h after CCl4 (0.2 ml/kg, s.c.) administration. Serum ALT rose following CCl4 administration, while liver cytochrome P-450 and b5 levels and serum T3 which reflects the liver microsomal thyroxine-5'-deiodinase activity (1) fell. Intraperitoneal administration of dantrolene sodium (5 mg/kg), 1 h before CCl4 s.c., suppressed CCl4-induced elevation of the serum ALT significantly. However, levels of P-450, b5, and serum T3 were not significantly different between dantrolene-treated and untreated groups. These results suggest that dantrolene sodium has a protective effect on CCl4-induced liver injury through a mechanism unrelated to these liver microsomal functions.