The inhibitory effects of some pesticides on human erythrocyte carbonic anhydrase activity (in vitro)

Abstract

The effects of Folidol(TM) [O,O-dimethyl O-(4-nitrophenyl) phosphorothionate; methyl parathion], Amin'a(TM) [dimethylamine salt of 2,4-D; 2,4-dichlorophenoxy acetic acid dimethylamine], Trimidal(TM) [alpha-(2-chlorophenyl)-alpha-(4-fluorophenyl)-5-pyrimidine-methanol], Fusilade(TM) [fluazifop-p-butyl; R-2-[4-((5-trifluoromethyl)-2-pyridinyl)oxy) phenoxy)propanate] and Rubigan(TM) [alpha-(2-chloro-phenyl)-alpha-(4-chlorophenyl)-5-pyrimidinemethanol; Fenarimol], which are commonly used in agricultural fields, have been investigated on human erythrocyte carbonic anhydrase isoenzymes (HCA-I, HCA-II) in vitro. Isoenzymes employed in the study were purified by using Sepharose-4B-L-tyrosine-sulphanylamide affinity gel. All the pesticides evaluated inhibited the activity of isoenzymes to various degrees. 150 values of chemicals caused inhibition were determined by means of activity percentage-[I] diagrams. These values of Folidol(TM), Amin'a(TM), Trimidal(TM), Fusilade(TM), Rubigan(TM) for CA-I and CA-H were 5.25 x 10(-4) and 3.60 x 10(-4), 4.74 x 10(-4) and 2.65 x 10(-4), 1.84 x 10(-3) and 1.36 x 10(-5), 1.18 x 10(-4) and 5.89 x 10(-5), 8.91 x 10(-4) and 6.99 x 10(-5), respectively. Trimidal(TM), Fusilade(TM) and Rubigan(TM) were the most effective inhibitors for CA-H isoenzyme. The inhibition of Trimidal(TM) was quite higher to CA-II than CA-I, although Folidol(TM) and Amin'a(TM) showed similar inhibition effects on CA-I and CA-H activities.