Cardiotoxic effects of venoms from Chironex fleckeri and Chiropsalmus sp. on an invertebrate model

T Carrette,J Seymour

doi:10.1590/s1678-91992006000200007

Abstract

Extracted venoms from two species of cubozoan, Chironex fleckeri (C. fleckeri)and Chiropsalmus sp., were injected into the freshwater crayfish Cherax quadricarinatus (C. quadricarinatus). By means of a Vascular Doppler, the cardiac parameters heart rate and contraction amplitude were recorded, with the theoretical total heart output calculated from these two recordings. Cherax quadricarinatus reflects prey items utilized by these two species in the wild and so comparisons of venom action on this animal have greater ecological relevance than those of previous mammalian models used. While the results of this study reflect previous research showing that the overall potency of C. fleckeri venom is greater than that of Chiropsalmus sp. venom, the action of the venoms on the heart muscle is found to be different. Chironex fleckeri,which has the most potent venom out of these two species, is actually less effective in reducing cardiac activity than Chiropsalmus sp., which may be a direct reflection of the variation in primary prey utilized by each species.

Highlights

Previous studies into venom from Chironex fleckeri have shown cardiac effects such as bradycardia produced in an assortment of predominantly vertebrate models [10, 11, 13], with comparable bradycardia having been reported for Chiropsalmus sp. venom, likewise tested on vertebrate models [13]
Heart rates of animals injected with C. fleckeri venom were approximately 75% of their original rate compared to the 50% decrease in heart rate for animals injected with Chiropsalmus sp. venom
The relative heart rate in experimental animals decreased at a distinctly slower rate after injections of C. fleckeri venom than that of animals injected with Chiropsalmus sp. venom

Summary

Introduction

Previous studies into venom from Chironex fleckeri have shown cardiac effects such as bradycardia produced in an assortment of predominantly vertebrate models [10, 11, 13], with comparable bradycardia having been reported for Chiropsalmus sp. venom, likewise tested on vertebrate models [13]. Previous studies into venom from Chironex fleckeri have shown cardiac effects such as bradycardia produced in an assortment of predominantly vertebrate models [10, 11, 13], with comparable bradycardia having been reported for Chiropsalmus sp. For all the research into the venom of cubozoans, no study has investigated the changes that occur in the cardiac muscles of a relevant prey type after envenoming. On a whole invertebrate animal model similar to prey items utilized by both species in the wild. It serves to examine the venom action from an ecological perspective and compare this to previous venom research predominantly focused on venom actions on terrestrial vertebrates and isolated muscle preparations

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Conclusion