Kinetic Evaluation of (11)C‐1‐Aminocyclopentane Carboxylic Acid in Rabbits Bearing VX‐2 Tumors Using Positron Emission Tomography

Tumor detection with (11)C‐1‐aminocyclopentane carboxylic acid ((11)‐ACPC) showed that this amino acid has a high affinity for malignant tumors. We studied the kinetics of intravenously injected (11)C‐ACPC in the rabbit VX‐2 tumor using positron emission tomography. Three female rabbits bearing VX‐2 tumor in the thighs were used. High uptake of (11)C‐ACPC was seen in the tumor and liver. (11)‐ACPC in plasma decreased rapidly after injection and its activity in the tumor increased with time. The kinetic evaluation of ACPC uptake into the tumor was performed using the unidirectional transport model. The average values of the transfer constant of (11)C‐ACPC for VX‐2 tumor were 0.030±0.002 ml/min/g. This preliminary result may form the basis for a quantitative analysis of the in vivo distribution of (11)C‐labeled ACPC in tumors.