11C-PHNO

**11C-PHNO** is a radiopharmaceutical imaging agent, specifically a positron emission tomography (PET) radiotracer, used to image **dopamine D2 and D3 receptors** in vivo in humans. It is an **agonist ligand** with a higher affinity for the dopamine D3 receptor compared to the D2 receptor, enabling it to map and quantify these receptor subtypes in the brain and other tissues using PET imaging. Because 11C-PHNO acts as an agonist, its in vivo binding is more sensitive to endogenous dopamine fluctuations than antagonist tracers, making it highly useful for detecting changes in synaptic dopamine and for evaluating neurochemical differences in psychiatric and neurodegenerative disorders. **11C-PHNO** has been used predominantly in research settings to study the dopamine system in the context of schizophrenia, Parkinson's disease, addiction, and more recently, to assess pancreatic beta cell mass in diabetes due to the presence of dopamine receptors in pancreatic tissue[1][2][3][4][5][8].

Other names

11C-(+)-PHNO[11C]-PHNO(11)C-PHNO