BIOCHEMICAL STUDIES OF AN UNNATURAL AND ANTITUMOR AMINO ACID: 1-AMINOCYCLOPENTANECARBOXYLIC ACID: I. TOXICITY AND TISSUE DISTRIBUTION

Abstract
The unnatural amino acid 1-aminocyclopentanecarboxylic acid (ACPC) is toxic to rats when given at concentrations of above 0.1% in the diet, or in successive 50 mg/kg daily intraperitoneal injections. A single injection of 300 mg/kg did not kill any rats. After injection, the concentration of ACPC in the blood of the animals was constantly low and the urinary excretion was also very slow. Using radioactive ACPC, it was found that the substance was widely distributed in the tissues and while it was never incorporated into the proteins, it was always found in the cellular fluid.