The investigation of the effects of nitro derivatives of pyrazol carboxylic acids on bovine carbonic anhydrase enzyme

Carbonic anhydrases (E.C. 4.2.1.1.) are family of zinc metalloenzymes that catalyze the reversible hydration of carbon dioxiede in a two-stop reaction to yield bicarbonate and proton. The isoenzymes of human eye are CA-I, CAII and CA-IV. Carbonic anhydrase inhibitors, which reduce aqueous production with a corresponding decrease in intraocular pressure (IOP), have been used as ocular hypotensive agents for the treatment of glaucoma.In this study, new carbonic anhydrase inhibitors's effects on carbonic anhydrase enzyme as candidates for treatment of glaucoma were investigated.First, carsonic anhydrase enzymes from bovine erythrocyte were, purifed using affinity gel and all of the investigations were carried out with these enzymes.Later, inhibition effects of these new compounds (4, 5, 6) on bovine carbonic anhydrase enzymes (BCA) have been investigated in vitro. In the studies, it was taken advantage of hydrates and esterase activites for determining of carbonic anhydrase activitates. It was observed that (4, 5, 6) compounds show inhibition effect on BCA hydratase and esterase activity. I50 values were determined by drawing % activity-[I] graphs for drugs showing inhibition effects. For (4), (5), (6), compounds of CO2-hydratase activity, inhibition effect ranged from 0,52.10-7 to 1,79.10-7 M for BCA with I50 (molarity of inhibitor producing a %50 inhibition of CA activity). As for esterase activity of p-nitrophenyl acetate, (4), (5), (6) compounds have inhibition ranging from 1,44.10-7 to 3,91.10-7 M for BCA with I50.Key Words: Glaucoma, I50 Values, Carbonic Anhydrase, Sulfonamides