Fig. 7.

5′GNTI treatment did not affect somatic signs of naloxone-precipitated or spontaneous withdrawal. (A) All of the rats were handled and habituated to subcutaneous saline injections for 1 week. All of the rats then received heroin (2–6 mg/kg, SC) 5 days per week for 4 weeks. On the third week, half of the rats received vehicle, and half received 5′GNTI (30 mg/kg, SC). Twenty-four hours later, all of the rats received naloxone hydrochloride (1 mg/kg, SC) and were observed for signs of somatic withdrawal for 10 min. After 1 week, 4 h after the heroin injection, the rats were observed for signs of spontaneous withdrawal. Treatment with 5′GNTI in female (B) or male (C) rats did not change naloxone-precipitate or spontaneous signs of heroin withdrawal. The data are expressed as mean ± SEM and were analyzed using unpaired Student's t-test. n = 7–8/group. SWT, somatic withdrawal test.