Nerve agents rabbits

Callaway, S., Dimhuber, P. (1971). Estimation of the concentration of nerve agent vapour required to produce measured degrees of miosis in rabbit and human eyes. Technical Paper No. 64. Chemical Defence Research Estahlishment, Porton Down, Salisbury, Wiltshire, UK. 

RBC AChE activity also varies among species. In humans, low RBC AChE activity has been associated with increased susceptibility to nerve agents (Leng and Lewalter, 1999). Pigs, sheep, dogs, rabbits, and cats have less RBC cholinesterase activity than humans (Anonymous, 2000b Ellin, 1982). This would make these species more sensitive to nerve agents unless they have an alternative system to combat cholinesterase inhibition. 

Even though the lethal nerve agent exposure level for animals may be higher than that for humans, it is still possible that animals eould exhibit other nonlethal effects sooner and more notieeably than humans. Rabbits develop 90% miosis at a lower inhaled eoneentration of cyclohexyl sarin when compared to humans (2.71 mg.min/m versus 13.85 mg.min/m ) (NRC, 2003). 

Pyridostigmine bromide studies have been performed in dogs, guinea pigs, monkeys, rabbits, rats, and mice. Diarrhea, salivation, tremors, and respiratory failure were seen prior to death. Side effects of the drug are related to muscarinic and nicotinic effects. Toxicity is also related to cholinergic stimulation. Effectiveness of pretreatment to reduce lethality after exposure to nerve agents (in particular, soman) is dependent on the administration of atropine and pralidoxime, postexposure. 

In another study, clipped rabbits were exposed to sulfur mustard, lewisite (L), thickened soman, and VX and were decontaminated between 30 s and 5 min postexposure. Eor the vesicants (sulfur mustard and L), lesion areas were compared. Decontaminating for 1 min resulted in the lesion areas being reduced 21-fold for sulfur mustard and 22-fold for L, relative to no decontamination. For the nerve agents (soman and VX), the inhibition of blood acetylcholinesterase (AChE) was used as a marker. Using a 2 min decontamination time, the dose of nerve agent required to produce 50% inhibition of AChE was increased 1.8-fold for thickened soman and 18-fold for VX (Hobson et al., 1993). 

MOD26. Estimation of the concentrations of nerve agent vapour required to produce measured degrees of miosis in rabbit and human eyes. Unpubhshed MOD report. 

Fig. 6. Summarization of results correlating inhibition efficacy (piso) and toxicity (log LD50) for some OP and nerve agents. Equation y = 9.87 — 1.26x p < 0.01 rxy = —0.9489. The lines indicate experimentally determined piso (human brain AChE) values (axe y) or extrapolated values (axe x) of LD50 for systox and VX. Each point represents the value of piso corresponding to LD50 value for rabbit, rat, guinea pig, mouse, and dog. The compounds under code are designated by the abbreviation of the oxyalkyl group on the phosphorus head, and by the alkyl on the nitrogen atom - e.g. VX is designated as Et-iPr (modified from B11, B14 and P3).

Valiyaveettil, M., Alamneh, Y, Biggemann, L., et al., 2010. Efficient hydrolysis of the chemical warfare nerve agent tabun by recombinant and purified human and rabbit serum paraoxonase. Biochem. Biophys. Res. Commun. 

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