Fig. 6. Effect of competing drugs (1 mg kg⁻¹; PK11195, PBR316, Ro 5-4864, and flumazenil) on [¹⁸F]PBR316 uptake in peripheral organs and skull of rat at 1 h p.i. results are mean ± SD, unit is % injected dose per g tissue, n = 4 controls and n = 3–4 treated animals. (*p < 0.01).