Fig. 6.

(A) 5′GNTI had no effect on heroin withdrawal-induced hyperalgesia 30 min after treatment. Half of the rats received saline, and half received heroin (2–6 mg/kg, SC). Four hours later, all of the rats received vehicle and were tested after 30 min in the von Frey test. Two days later, the same rats received 5′GNTI (30 mg/kg, SC) and were tested 30 min later in the von Frey test. The data are expressed as mean ± SEM and were analyzed using a two-way ANOVA. *p < 0.05, main group effect. n = 9–10/group. gf, gram force. (B) Plasma and brain 5′GNTI levels. Wistar rats of both sexes received 5′GNTI (30 mg/kg, SC), and brain and plasma were collected 30 min or 24 h later. Samples were analyzed by mass spectrometry. The data are expressed as mean ± SEM and were analyzed using a one-way ANOVA followed by the Bonferroni post hoc test. ▲, males. ▼, females. *p < 0.05, difference between groups. n = 4/group.