L-arginine phosphate

Endpoint summary

Link to relevant study record(s)

Reference

Endpoint:

basic toxicokinetics, other

Type of information:

other:

Adequacy of study:

other information

Justification for type of information:

Based on human data in the literature, supplemental L- arginine is readily absorbed in the body. About half of the ingested L- arginine is rapidly converted to ornithine, primarily by the enzyme arginase. In addition, L- arginine is a precursor for the synthesis of proteins, as well as nitric oxide, urea, creatine, and agmatine. L- arginine turns over rapidly in mammals. Half -lives in the circulation of 1.06, 0.75, and 0.65 h have been reported for adult, pregnant, and neonatal pigs, respectively. After oral administration, L-arginine is subject to extensive presystemic and systemic elimination, i.e. by bacteria in the gut and arginases in the gut and liver, respectively. Hence, l-arginine treatment is hampered by the extensive presystemic elimination due to intestinal arginase activity (Schwedhelm et al. 2007). L- arginine catabolism to urea by highly active arginase in the gut of adults is fast, and only 60% of oral arginine evades this intestinal metabolism. Another 15% of circulating arginine is metabolized in the liver. (See WOE for reproductive toxicity)

Description of key information

Based on analogue approach, basic toxicokinetics of L- arginine phosphate are expected to be similar to L- arginine.