RESUMO
The purpose of the present study was to investigate the biodistribution profile of the venom of Hemiscorpius lepturus, the most dangerous scorpion in Iran. Blood and tissue samples were taken at various predetermined intervals during a 400-minute period for the venom and a 360-minute period for the antivenom in rats. The radio-iodination was carried out using the chloramine-T method. The results showed that the descending order of venom uptake was skin, kidneys and intestine, respectively. The descending order of polyclonal antivenom uptake was kidneys, intestine, heart and lungs. The calculated pharmacokinetic parameters of the venom were Telimination half-life = 521.5 ± 12.6 minutes; Vd/F (apparent volume of distribution) = 14.9 ± 3.3 mL; clearance (CL/F, apparent total clearance of the drug from plasma) 0.02 ± 0.005 mL/minute and for the antivenom Telimination half-life = 113.7 ± 7.4 minutes; Vd/F = 13 ± 1.2 mL and CL/F 0.08 ± 0.01 mL/minute. The pharmacokinetics profile comparison of the venom with that of the antivenom shows that serotherapy may be more effective if administered within 2-4 hours following envenomation by H. lepturus.(AU)
Assuntos
Venenos de Escorpião , AntivenenosRESUMO
The available Razi Institute antivenom is still, empirically, used by intramuscular (IM) administration for the treatment of scorpion stings in humans by six medically dangerous species including Hemiscorpius lepturus (H. lepturus). The aim of this study was to assess the neutralizing ability and effectiveness of the antivenom in inhibiting hemoglobinuria, biochemical changes, increased microalbuminuria and urinary lactate dehydrogenase (LDH) following H. lepturus sting. Simultaneous intramuscular administration of 10 μL and 100 μL of antivenom, after 24 hours, had no significant preventive effect on the extent and degree of hemoglobinuria or proteinuria produced in venom-treated rats. After IM administration of antivenom, no significant changes in decreased red blood cell (RBC) count and hemoglobin were observed. Immediate intramuscular administration of 10 μL of antivenom had no significant effects on both LDH and microalbuminuria. The present findings did not present correlation with clinical signs. Therefore, to fully assess the efficacy of the available antivenom and make appropriate recommendations, more in vivo or in vitro investigations including antigen-antibody interaction, enzymatic analysis and route-dependent administration are required.(AU)