In vivo metabolism of beta-N-oxalyl-L-alpha,beta-diaminopropionic acid: the Lathyrus sativus neurotoxin in experimental animals.

A comparative study of the metabolism of 1,2,3 (14)C-ODAP and 4,5 (14)C-ODAP in mice, rats and chicks has been carried out. Following oral administration of 1,2,3 (14)C-ODAP to either black or white mice, nearly 16% of the radioactivity appeared in the expired CO2 within 8 h, while in the rat only 3% of it appeared and in chicks it was less than 2%. No 14CO2 appeared in the expired air in mice given 4,5 (14)C-ODAP. Electrophoregrams of the spot urine samples from the animals given 1,2,3 (14)C-ODAP showed the presence of one radioactive metabolite (metabolite-1) in addition to ODAP. While the urine from rats and mice given 4,5 (14)C-ODAP indicated the presence of metabolite-1 as well as 14C-oxalate, in chicks, however, no 14C-oxalate was present and only metabolite-1 could be detected. The results indicate that ODAP can to some extent undergo oxidation in vivo in mice (and to a lesser extent in rats) leading to the formation of CO2 and oxalate and a similar pathway might be more prominent in humans leading to a near complete oxidation of ODAP.