Figure 4. Concentrations of plasma metabolites at 3 different stages. (A–D) omega-6 and omega-3 polyunsaturated fatty acids. (E–H) representative fatty acid, amino acids and organic acid. (I–L) metabolites that have not recovered after long-term heroin withdrawal (*P < 0.05, **P < 0.01, ***P < 0.001, compared with healthy controls. #P < 0.05, ##P < 0.01, ###P < 0.001, compared with acute heroin withdrawal). Note: dihomo-gamma-linolenic acid is the polyunsaturated fatty acid with the most significant difference, tyrosine is the neurotransmitter precursor with the most significant difference, and oxoglutaric acid is the organic acid with the most significant difference in energy metabolism.