Ricin toxicity

Preliminary studies indicate that ricin induces an oxidative stress in the livers of mice (Muldoon and Stohs, 1991). Few studies have examined other biochemical alterations that may be associated with ricin toxicity. Oxidative stress, induced by free radicals and reactive oxygen species, has been widely implicated as a mechanism in the toxicity of ricin (Muldoon and Stohs, 1991 Omar et al, 1990). 

The importance of carbohydrate binding for ricin toxicity is supported by the observation that cell lines lacking galactosyl transferase are resistant to ricin (Foddy and Hughes, 1986). The potency of ricin or related toxins does not correlate directly, however, with the number of receptors present... 

The B-lymphocytes may represent one of the preferential targets of ricin toxicity in vivo. Lymphatic tissues from animals exposed to ricin show extensive hyperplasia and cellular necrosis with edema, hyperemia, and hemorrhage (Waller et al., 1966). Rats injected (i.m.) with ricin or abrin develop numerous apoptotic-like bodies in ileal crypts, para-aortic lymph nodes, and Peyer s patches (Griffiths et al., 1987). The finding of apoptosis in whole animals may be due to a direct effect of ricin on cells of the lymphatic tissue, as is observed with isolated cells in vitro, or it may partly reflect the numerous pathological sequelae of toxin exposure, including severe shock (Griffiths et al., 1988 Howat, 1988). 

Lemley, P.V., Amanatides, P. and Wright, D.C. (1994) Identification and characterization of a monoclonal antibody that neutralizes ricin toxicity in vitro and in vivo. Hybridoma, 13, 417 421. 

Wesche, J., Rapak, A. and Olsnes, S. (1999) Dependence of ricin toxicity on translocation of the toxin A-chain... 

EXPERIMENTAL STRATEGIES FOR PROTECTING AGAINST RICIN TOXICITY... 

Thompson W, Scovill J, Pace J. Drugs that show protective effects from ricin toxicity in in-vitro protein synthesis assays. Natural Toxins. 1995 3 369-377. 

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