ISSN 1214-0287 (on-line)
ISSN 1214-021X (printed)

Volume 2 (2004), No 2, p 117-122

A comparison of protective and anticonvulsive efficacy of two prophylactic mixtures in soman-poisoned rats

Ivan Samnaliev, Jiri Kassa

Address: Jiri Kassa, P. O. Box 35/T, Purkyne Military Medical Academy, 500 11 Hradec Kralove, Czech Republic

Received 27th February 2004.
Revised 18th March 2004.
Published online 20th April 2004.

Full text article (pdf)

The protective and anticonvulsive efficacy of two prophylactic mixtures (PANPAL consisting of pyridostigmine, benactyzine, and trihexyphenidyle and pyridostigmine plus biperiden) administered prior to the administration of soman in a lethal dose (1.5 LD50) with or without antidotal treatment (atropine + HI-6) was evaluated using rats as experimental animals. The pretreatment was applied 30 and 60 min before intoxication and the antidotal therapy was administered 1 min after soman poisoning. The anticonvulsive efficacy of both prophylactic combinations was determined using a seven degree scale. Non-treated soman-poisoned rats died within 10 min after soman challenge showing severe tremor, subconvulsions and generalized convulsions. More than 90% of pretreated animals survived for 24 hrs following soman poisoning and they were observed to be free from soman-induced toxic signs 24 hrs after soman administration. Our findings confirm that both prophylactic mixtures are able not only to protect experimental animals from the lethal effects of soman but also to eliminate most soman-induced toxic signs. Our results confirm that both prophylactic mixtures should be considered as a pretreatment for nerve agent poisoning, especially in the case of the threat of exposure to soman.

soman; antidotal treatment; convulsion; prophylactic mixture; rat

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