Arginase and PET

Arginase is a metalloenzyme that catalyses the hydrolysis of L-arginine to L-ornithine and urea. Cytosolic arginase type I (Arg1) is expressed predominantly in the liver. Arginase type II (Arg2) is expressed in mitochondria throughout extrahepatic tissues. Arginase competes for L-arginine with nitric oxide synthases (NOSs) which produce vasodilator nitric oxide (NO).

Arginase overexpression is associated with cardiovascular disease, inflammation, and cancer. Therefore, arginase inhibitors have been developed for therapeutic use.

[18F]FBMARS is a arginase inhibitor that has shown selective arginase-mediated tumour uptake in a mouse model (Clemente et al., 2021).

See also:


Caldwell RW, Rodriguez PC, Toque HA, Narayanan SP, Caldwell RB. Arginase: a multifaceted enzyme important in health and disease. Physiol Rev. 2018; 98(2): 641–665. doi: 10.1152/physrev.00037.2016.

Dzik JM. Evolutionary roots of arginase expression and regulation. Front Immunol. 2014; 5: 544. doi: 10.3389/fimmu.2014.00544.


Updated at: 2023-01-20
Created at: 2021-11-29
Written by: Vesa Oikonen