Hemorrhagic activity of Bothrops venoms determined by two different methods and relationship with proteolytic activity on gelatin and lethality.
The changes in hemorrhagic activity, proteolytic activity on gelatin and the lethal potency of four Bothrops venoms treated at different pH values or with EDTA were studied. Venoms from B. alternatus, B. jararaca, B. moojeni and B. neuwiedii of Argentina were preincubated at pH 5.8, 5.1 or 3.8 or with EDTA and the hemorrhagic activity expressed as size of the hemorrhagic lesion or as the amount of hemoglobin extracted, the proteolytic activity on gelatin and the lethal potency were determined. Although the MHDs recorded in rats were 19-56 fold higher than those recorded in mice, the A(550) extracted per gram of hemorrhagic haloes was very similar in rats or mice independent of the venom dose. Inhibition of proteolytic activity after preincubation at pH 5.1 or 3.8, agrees with the decreased amount of hemoglobin extracted from the hemorrhagic haloes, and with the increase in mean survival time after the i.p. injection to mice. Preincubation with EDTA resulted in 80% inhibition of hemorrhagic activity of B. jararaca venom and complete inhibition with the other Bothrops venoms tested. Measurement of the amount of hemoglobin extracted gives significant information in comparative studies, not available by measurement of the size of hemorrhagic haloes.
de Roodt
Adolfo Rafael
AR
Instituto Nacional de Producción de Biológicos-ANLIS, Dr Carlos G Malbrán, Av Vélez Sarsfield 563, CP 1281, Buenos Aires, Argentina. aderoodt@uolsinectis.com
Litwin
Silvana
S
Vidal
Juan Carlos
JC
D000818:Animals; D017837:Bothrops / Q000378:metabolism*; D003435:Crotalid Venoms / Q000201:enzymology / Q000633:toxicity*; D004492:Edetic Acid / Q000494:pharmacology; D005780:Gelatin / Q000378:metabolism*; D006454:Hemoglobins / Q000378:metabolism; D006470:Hemorrhage / Q000139:chemically induced*; D006863:Hydrogen-Ion Concentration; D007928:Lethal Dose 50; D051379:Mice; D010447:Peptide Hydrolases / Q000378:metabolism* / Q000633:toxicity; D051381:Rats; D016019:Survival Analysis
D003435:Crotalid Venoms; D006454:Hemoglobins; D005780:Gelatin; D004492:Edetic Acid; D010447:Peptide Hydrolases