Fig. 3

Effect of self-administration of morphine on D1 receptor expression in glutamatergic projection neurons from the mPFC to the BLA using triple-immunofluorescence method. a The self-infusion number during the period of morphine self-administration. b The averaged optical density of D1R in the glutamatergic terminals from the mPFC to the BLA in saline and morphine self-administration groups (n = 6, *P < 0.05, compared to saline group). Data are shown as the mean ± SEM