Identification of Hypoglycemia in Mice as a Surrogate Marker of Ricin Toxicosis

Purpose: In an effort to develop a non-lethal model of ricin toxicosis, we studied the biochemical effects of the administration of ricin in mice.Methods: Mice received an intraperitoneal injection of ricin toxin, after which a panel of 21 biochemical parameters was determined. Effect of ricin administration on blood glucose concentration was studied in greater detail. To determine whether results of biochemical analyses correlated with therapeutic manipulations known to protect against ricin toxicosis, the effect of immunization on blood glucose values after ricin administration was studied.Results: Of the biochemical parameters studied, only blood glucose and amylase values were affected by ricin administration. Because blood glucose concentration can be easily and instantaneously measured on 25 to 50 μl of blood, using handheld instruments, this parameter was further evaluated. A dose- and time-related decrease in blood glucose concentration was documented. Mice immunized with ricin had smaller changes in blood glucose concentration than did non-immunized animals after ricin administration.Conclusion: Blood glucose concentration may be used as a surrogate for lethal challenge as a measure of ricin toxicosis after its systemic administration.