Figure 4: Affinity labeling of D2R with azidocleopride (N3) using UV or gamma rays. Irreversible and specific binding to peripheral benzodiazepine receptor, D2R, is noted after exposure of the mixture of D2R and 1 uM N3 under UV or gamma rays. Statistically significant correlations of binding to N3 ( , ) and gamma rays doses ( , ) are revealed by two-way ANOVA.