Quantitative Determination of Hemorrhagic Activity in the Venom of the Peruvian Snake Bothrops barnetti
Aguirre, Carlos1; Zavaleta, Alfonso1,3; Salas, María1 and García, Jaime2
1Laboratorio de Farmacología, Departamento de Ciencias Fisiológicas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia. A.P. 5045, Lima 100 2Departamento de Física y Matemáticas, Facultad de Ciencias y Filosofía, Universidad Peruana Cayetano Heredia; 3Instituto de Medicina Tropical Alexander von Humboldt, Universidad Peruana Cayetano Heredia. Perú.
We modified Kondo et al. (1960) technique, using guinea pig (Cavia aperea varporcellio) as an experimental animal for the semi-quantitative determination of hemorrhagic activity induced by snake venom. The Minimal Hemorrhagic Dose (MHD) is estimated using the logarithm of the dose and the mean diameter of the hemorrhagic lesions (MHD) by regression analysis and linear correlation, and error experimental determination for the mathematical evaluation of both subject and experimental effects. The Minimal Hemorrhagic Dose (MHD) was defined as the minimal dose producing a lesion 10 mm mean hemorrhagic diameter 24 hours after subcutaneous injection in the abdominal skin of a guinea pig.
This model, tested with lyophilized venom from Peruvian Bothrops barnetti at doses producing lesions ranging from 9 to 30 mm diameter, showed best linearity in the range between 10 and 20 mm. The Minimal Hemorrhagic Dose (MHD) for this venom was 0.87 mg (fiduciary limits at 99% of probability were 0.57 and 1.32 mg).
Key words: hemorrhage, snake venom, Bothrops barnetti, guinea pig model.
Introduction:Bothrops bametti accounts for most envenomings in the Northern Coast of Peru. (Uribe, 1985) Its venom causes edema, local hemorrhage, myonecrosis, and coagulation defects due to a lowering of circulating fibrinogen levels in experimental animals. lncio and lncio have recently reported a higher hemorrhagic activity in the venom of Bothrops bametti than in that from other medically important snakes from Peru: Bothrops atrox, Bothrops pictus, and Lachesis muta. Little is known about the pharmacology and biochemistry of this venom.
Kondo et al. (1960) proposed a method for the determination of the hemorrhagic activity of Trimeresurus flavoviridis venom. This method was officially adopted by the World Health Organization (WHO, 1981) and is widely used today. Serious experimental and statistical imprecisions were detected in the original publication, prompting us to develop a new method, using the guinea pig (Cavia aperea varporcellio) as an experimental animal. This study shows that the guinea pig is an appropriate model for the study of hemorrhagic activity, establishes an experimentally and statistically convenient new working range for this purpose, and updates the statistical treatment of the experimental data, using Linear Regression analysis and determination of lack of fit and pure error through one-way analysis of variance for the determination of Minimal Hemorrhagic Dose (MHD).
Publication Dates
-
Publication in this collection
08 Oct 2002 -
Date of issue
Dec 2001
