Soman toxicity

M. Jokanovic, Liver Esterases and Soman Toxicity in the Rat Following Partial Hepatectomy , Biochem. Pharmacol. 1990, 39, 797-799. 

Jimmerson, V.R. T-M. Shih and R.B. Mailman. 1989. Variability in soman toxicity in the rat Correlation with biochemical and behavioral measures. Toxicology 57 241-254. 

Maxwell, D.M., K.M. Brecht and D.E. Lenz. 1987b. Effect of carboxylesterase inhibition on carbamate protection against soman toxicity. Proc. Sixth Chem. Def. Biosci. Rev., pp. 17—24. (cited in Somani et al., 1992)... 

Maxwell, D.M., Brecht, K.M., O Neill, B.M. (1987). The effect of carboxylesterase inhibition on interspecies differences in soman toxicity. Toxicol. Lett. 39 35-42. 

Jokanovic, M. (1990). Liver esterases and soman toxicity in the rat following partial hepatectomy. Biochem. Pharmacol. 39 797-9. 

Some interesting results on soman toxicity, thyroid deficiency, and plasma CarbE were reported by Swisher et al. (1986). They observed reduced effect of soman intoxication in hypothyroid rats with respect to both seizure aetivity and lethality. The resistanee to soman was ascribed to inereased binding of soman to plasma proteins, since both ChE and CarbE (tributyrinase) of plasma displayed nearly two-fold higher activity in hypothyroid than euthyroid rats. The latter result inspired us to investigate hypothyroid rats with respeet to possible parallel eoregulation of CarbE and ChE in plasma and liver. Plasma ChE is undoubtedly synthesized in liver (Augustinsson, 1948 Koelle, 1963) and the ChE aetivity in rat plasma as well as liver is known to differ between males and females (Leeuwin, 1966 Edwards... 

The various isoenzymes of plasma CarbE might have different importance with respect to their scavenger function. Results show a 2.5-fold higher plasma CarbE activity with methyl butyrate in adult female rats compared to males, whereas the soman toxicity does not differ between them (Sterri et al., 1985a). The same authors also report adult values of soman toxicity in 31 day old rats of both sexes, whereas at that time the methyl butyrate hydolyzing capacity of female plasma is far from fully developed. Thus, the isoenzyme with the highest preference for 4-nitrophenyl butyrate as substrate (Sterri and Foimum, 1989) may be the most effective soman scavenger of plasma, at least in rats. 

The effect on soman toxicity by pyridostigmine prophylaxis in different species could in principle also be explained by the CarbE concept of Sterri and Fonnum (1989). This means that the protection factors of carbamate prophylaxis as calculated for the different species were similar to the experimental protection factors of pyridostigmine prophylaxis against soman as observed for rat and guinea pig (Gordon et al, 1978) as well as marmoset and rhesus monkey (Dimhuber et al, 1979). Thus, due to the CarbE concept, we were fairly convinced that the hiunan species would achieve a similar protection by pyridostigmine prophylaxis as rhesus monkey, since both species lack the... 

Doctor, B.P., Blick, D.W., Caranto, G., Castro, C.A., Gentry, M.K., Larrison, R., Maxwell, D.M., Murphy, M.R., Schutz, M., Waibel, K., Wolfe, A.D. (1993). Cholinesterases as scavengers for organophosphoms compounds protection of primate performance against soman toxicity. Chem. Biol. Interact. 87 285-93. 

Sterri, S.H., Berge, G., Fonnum, F. (1985a). Esterase activities and soman toxicity in developing rat. Acta Pharmacol. Toxicol. 57 136-40. 

Gupta RC and Dettbarn WD (1987) Iso-OMPA-induced potentiation of soman toxicity in rat. Archives of Toxicology 61 58-62. 

Maxwell DM and Koplovitz I (1990) Effect of endogenous carboxylesterase on HI-6 protection against soman toxicity. The Journal of Pharmacology and Experimental Therapeutics 254 440—444. 

Lallement, G. et al. Subchronic administration of various pretreatments of nerve gas poisoning n. Compared efficacy against soman toxicity. Drug Chem. Toxicol, 24, 165, 2001a. 

Lim, D.K. et al. Prevention of soman toxicity after the continuous administration of physostigmine, Pharmacol. Biochem. Behav., 31, 482, 1988. 

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