Haemorrhagic activity of Neotropical rattlesnake (Crotalus vegrandis Klauber, 1941) venom

Abstract

In this work we have demonstrated for the first time in any Venezuelan Crotalus, haemorrhagic activities that are present in the Neotropical Uracoan rattlesnake (Crotalus vegrandis) venom. This venom has been little studied, perhaps because the snake is restricted to a small habitat located in the dry savannahs of northeastern Venezuela. In our experiments Crotalus vegrandis venom caused a very evident haemorrhagic area consisting of approximately 2/3 diameter of the area caused by a positive control Bothrops lanceolatus venom. Crotalus vegrandis venom affects blood coagulation and causes intense haemorrhages. It does not clot fibrinogen, therefore it has neither thrombin‐like activity which transforms fibrinogen to fibrin nor procoagulant enzymatic function which produces thrombin. On the other hand, it degrades fibrinogen making it incoagulable to thrombin. The venom, when injected in the animals, resulted in a high increase of the Partial Time of Thromboplastin (PTT) tests. It is interesting to observe that the haemorrhagic capacity in the Crotalus genus (widely distributed in the American continent) increases from south to the north, being present in North American Crotalus, a venom with wide haemorrhagic activities, and almost non‐existent in most of the South American Crotalus species and subspecies. Copyright © 1998 John Wiley & Sons, Ltd.

A low-cost method to test cytotoxic effects of Crotalus vegrandis (Serpentes: Viperidae) venom on kidney cell cultures

“…The myotoxic activity can be followed by skeletal muscle damage and the release of creatinophosphokinases (CPK), lactic dehydrogenase (LDH) and myoglobin. Hemorrhage is another common problem in many species of venomous snakes 1,14,19,21 . All the above activities could cause renal lesions.…”

“…In the present study, the activities of crude, hemorrhagic and neurotoxic fractions of C. vegrandis venom were evaluated on renal cells maintained in vitro and compared to Vero cells. This venom is of particular interest, since it is extremely hemorrhagic which is an uncommon condition of South American rattlesnake venom 19 .…”

Proteomic analysis of the rare Uracoan rattlesnake Crotalus vegrandis venom: Evidence of a broad arsenal of toxins

“…The C. vegrandis venom is known to be highly hemorrhagic (local and systemic bleeding are major signs of Uracoan rattlesnake envenomation) and neurotoxic (causing death by respiratory paralysis) (Gir on et al, 2005;Guben sek et al, 1978;Rodriguez-Acosta et al, 1998;Scannone et al, 1978). A neurotoxic fraction described by Kaiser and Aird (1987) contains crotoxin-like proteins.…”

“…(Scannone et al, 1978) and 0.5 mg/g (i.m.) (RodriguezAcosta et al, 1998) in mice and that the hemorrhagic and neurotoxic activities (Guben sek et al, 1978;Rodriguez-Acosta et al, 1998;Scannone et al, 1978) can be ascribed to metalloproteases (Aguilar et al, 2001) and to a crotoxin-like heterodimer (Gir on et al, 2005) respectively. An accident case was reported, in which a great edema of the affected limb was described with no apparent neurological signals (Pifano and Rodríguez Acosta, 1995).…”

Intraspecies differences in hemostatic venom activities of the South American rattlesnakes, Crotalus durissus cumanensis, as revealed by a range of protease inhibitors

“…Crotalus venoms contain serine and metalloproteases, several of which participate in the pathogenesis of tissue alterations in the bitten site and hemorrhages in tissues far from the site of the bite, such as kidneys, heart, lungs and the central nervous system [21,22]. In the current Crotalus durissus venom and inhibitors Salazar et al 527 Data are expressed as mean AE SD (n ¼ 4).…”