Effect of the Synthetic Pyrethroid Deltamethrin on the Level of Sulfhydryl Groups in Rat Liver

S. CHESHMEDJIEVA¹, P. POPOVA², T. MODEVA¹, I. DIMITROVA² and Ya. PROFIROV¹

¹Institute of Animal Science, BG-2232 Kostinbrod, Bulgaria
²Institute of Biology and Immunology of Reproduction, BAS, BG-1113 Sofia, Bulgaria

Abstract

CHESHMEDJIEVA, S., P. POPOVA, T. MODEVA, I. DIMITROVA and Ya.PROFIROV, 1999. Effect of the synthetic pyrethroid deltamethrin on the level of sulfhydryl groups in rat liver. Bulg.J.Agric.Sci., 5: 511-514

The concentrations of total sulfhydryls (TSH), non-protein-bound sulfhydryls (NP-SH) and protein-bound sulfhydryls (PB-SH), as well as the activity glutathione S-transferase [EC 2.5.1.18] (GST) were determined in the liver of male Wistar rats, treated with 1/1000 and 1/100 of LD50 of the synthetic pyrethtoid deltamethrin [NRDC-161: (S)-a-cyano-m-phenoxybenzyl (1R, 3R)-3-(2,2-dibromovinyl)-2,2-dimethyl-cyclopropane-carboxilate] for ten days per os. It was established a significant decrease in the concentration of low-molecular thiols as a result of the treatmens - about 50 %, with 1/1000 of LD50 of deltamethrin (P < 0.01) and about 63 %, with 1/100 of LD50 of deltamethrin (P < 0.001). As a result of the treatment a considerable reduction in the specific cytosolic activity of GST, measured with o-dinitrobenzene as substrate, was observed. The alterations in thiol/disulfide ratio and glutathione S-transferase activity might play important roles in the toxicity and the detoxifying mechanism of the liver.
Key words: rat liver, total sulfhydryls, non-protein-bound sulfhydryls, protein-bound sulfhydryls, glutathione S-transferase, deltamethrin [NRDC-161: (S)-a-cyano-m-phenoxybenzyl (1R, 3R)-3-(2,2-dibromovinyl)-2,2-dimethyl-cyclopropane-carboxilate]
Abbreviations: TSH - total sulfhydryls; NP-SH - non-protein-bound sulfhydryls; PB-SH - protein bound sulfhydryls; GST - glutathione S-transferase; GSH - glutathione; GSSG - oxidized form of glutathione; G6PDH - glucose-6-phosphate dehydrogenase; GR - glutathione reductase