Fig. 5.

(A) Distance traveled and (B) time spent in the brightly-lit center of an open field among Tat(−) or Tat(+) mice (n = 8/group) following 0–4 weeks of exposure to DOX to induce HIV-1 Tat in the CNS. In a separate experiment, different groups of mice were exposed to 4 weeks of DOX and assessed for: (C) latency to enter and (D) time spent in the center of an open field (n = 12–14/group), (E) time spent on the open arms of an elevated plus maze (n = 8–9/group) and (F) latency to fall from an accelerated rotarod (inset depicts maximum RPM achieved; n = 8–12/group). In a separate experiment to assess whether Tat affects anxiety related to MOR activation, (G) the distance traveled and (H) the time spent in the brightly-lit center of an open field significantly differed between Tat(−) or Tat(+) mice (n = 6–10/group after 30 days of DOX treatment) following an injection of saline and an acute injection of morphine (10 mg/kg, i.p., −15 min). Data are presented as a percent of saline-induced behavior. * indicates significant difference from Tat(−) control mice, p < 0.05, Student's t-test. Dashed line indicates control level in G and H.