Abstract
The effects of dantrolene were investigated on carbonic anhydrase (CA) enzyme activities in in vitro human and in in vivo Sprague-Dawley rat erythrocytes. For in vitro study, human carbonic anhydrase-I (HCA-I) and -II (HCA-II) were purified by Sepharose 4B–L-tyrosine-sulfanylamide affinity chromatography, rats were used for in vivo study. In vivo and in vitro CA enzyme activity was determined colorimetrically using the CO2-hydration method of Wilbur and Anderson. Dantrolene (1.64×10−5—6.56×10−5 M) showed in vitro inhibitory effects on HCA-I and HCA-II hydratase activity, when determined using the CO2-hydratase method. 50% inhibitory concentration (IC50) was 4.09×10−5 M for HCA-I and 3.24×10−5 M for HCA-II. Rat erythrocyte CA activity was significantly inhibited by 10 mg/kg dantrolene for up to 3 h (p<0.001) following intraperitoneal administration. In conclusion, Dantrolene inhibited the carbonic anhydrase enzyme activity under in vitro and in vivo conditions.
