Detection and quantification of a β-neurotoxin (crotoxin homologs) in the venom of the rattlesnakes and from Mexico.

Snake venom may vary in composition and toxicity across the geographic distribution of a species. In the case of the three species of the Neotropical rattlesnakes and recent research has revealed that their venoms can contain a neurotoxic component (crotoxin homologs), but is not always the case. In the present work, we detected and quantified crotoxin homologs in venom samples from three species distributed across Mexico, to describe variation at the individual and subspecific levels, using slot blot and ELISA immunoassays. We found that all individuals analyzed had substantial percentages of crotoxin homologs in their venoms (7.6-44.3%). In contrast, lacked them completely and six of ten individuals of the species had low percentages (3.0-7.7%). We also found a direct relationship between the lethality of a venom and the percentage of crotoxin homologs it contained, indicating that the quantity of this component influences venom lethality in the rattlesnake .