Ophidism is a public health problem in tropical countries, occurring predominantly in rural areas. In Colombia, among the species responsible for snakebite envenomation, inflicting high mortality, is the Chocoan bushmaster, Lachesis acrochorda, better known locally by the names “verrugosa (warty)” and “pudridora (rot-causing)”. In this research, the cardiotoxic effect of the venom of L. acrochorda in male Wistar rats weighing 230 ± 20 g was evaluated. A statistical design of randomized blocks was implemented with three treated groups, injected with lyophilized venom (doses of 3.22 μg/g, 6.43 μg/g, 12.86 μg/g), and a control group injected with 0.9% saline solution. Electrocardiographic (ECG) recordings were taken from the anesthetized animals, revealing an increase in the amplitude of the P and T waves and an increase in the duration of the QT intervals in the electrocardiographic recordings. These increases were not observed in the control biomodels. In the analysis of the CK and CK-MB enzyme levels, increases were also observed in the levels of cardiac isoenzymes in the injected animals, but none in the control animals. The histopathological analyses carried out reveal that the injected animals showed effects such as interfibrillar and perivascular edema, cellular shortening of the cardiomyocytes, foci with tissue destructuring, and necrosis with contraction bands. In conclusion, the venom of the Lachesis acrochorda snake increases the P and T waves and the QT interval and increases the CK and CK-MB enzymes in the blood. Additionally, it causes interfibrillar and perivascular edema in the cardiac tissue, cardiocytolysis, and contraction bands.

La víbora pitviper o equis colorada, Bothrocophias colombianus, perteneciente a la familia Viperidae, subfamilia Crotalinae, es una especie de serpiente venenosa que se encuentra en las selvas húmedas de la costa Pacífica de colombiana, donde el desconocimiento de los efectos de su veneno dificulta enormemente la atención médica. Esta investigación es un esfuerzo por conocer los efectos del veneno de B. colombianus, comprendiendo mejor los efectos locales, mediante el cálculo de las dosis mínima edematosa (MED) y mínima hemorrágica (MHD), estableciendo la dosis letal en 50 (DL50) en ratones de la cepa CFW, y evaluando cualquier efecto sistémico derivado de la dosis mínima coagulante (MCD) en plasma sanguíneo humano. Los resultados revelaron que la DL50 de este veneno es de 199,5 μg veneno/ratón. Se observaron efectos hemorrágicos (1,06 ± 0,47 μg de ) y edematizantes (0,45 ± 0,15 μg), además de un ligero efecto coagulante (21,02 ± 0,82 μg). En conclusión, el cuadro clínico del envenenamiento causado por esta especie podría caracterizarse por fuertes alteraciones hemorrágicas y edematosas, y ligeras alteraciones en el proceso de coagulación.

Background: owing to the difficulties for accessing health centers and the limited availability of antivenoms in rural areas of Colombia, in many rural communities people rely on traditional medicine based on the use of plant extracts as a therapeutic resource for the snakebite envenoming. In the department of Nariño, the potential of these alexiteric plants is unknown. This work determined the cultural importance of Neurolaena lobata (L.) Cass., one of the plants most frequently used by the rural communities of Tumaco, municipality with high incidence of poisonings, and assessed the efficacy of an extract of this plant to inhibit toxic effects of the venom of the snake Bothrops asper. Methods: semi-structured interviews were conducted with 14 randomly sampled individuals and the Cultural Importance index (CI) of the plant was calculated. Phytochemical tests were carried out and a battery of biological assays was applied to determine the neutralizing capacity of the extract on the lethal, coagulant, hemorrhagic, and myotoxic activities of the venom. Results: the CI of this plant (0.0544) reflects its ethnobotanical value for the rural communities of Tumaco. The ethanolic extract from the leaves contains tannins, flavonoids, alkaloids, saponins, and sesquiterpene lactones. Neutralization assays revealed that the extract inhibited the coagulant activity of B. asper venom, but failed to inhibit the myotoxic, and lethal activities, and only partially reduced the hemorrhagic effect. Moreover, the extract showed toxicity when assessed for lethality and myotoxicity. Conclusions: despite the cultural importance of the plant, our experimental findings do not support the claim that the crude extract of N. lobata inhibits the toxicity of the venom of B. asper of Colombia. Keywords: Bothrops asper, Neurolaena lobata, alexiteric plants.