Figure 6.(A, B) Grip strength, (C) mechanical allodynia, and (D) thermal hyperalgesia and (B’ and D’) simple linear regression for circulating and central steroid hormones among young adult and middle-aged HIV-1 Tat-transgenic male mice [Tat(+)] or their non-Tat-expressing age-matched counterparts [Tat(−)]. Grip strength threshold for (A) forelimbs alone or (B) forelimbs and hindlimbs together. (C) Paw-withdrawal threshold (g) in an electronic Von Frey test. (D) Paw-withdrawal latency (s) in a thermal probe test. Simple linear regressions between (B’) circulating corticosterone and forelimbs and hindlimbs together or (D’) hippocampal allopregnanolone and paw-withdrawal latency. *main effect for Tat(+) mice to differ from Tat(−) mice. †main effect for middle-aged mice to differ from young adults. ^significant interaction wherein indicated group differs from young adult Tat(−) controls. Regression lines (solid) are depicted with 95% confidence intervals (dotted), (two-way ANOVA, p ≤ 0.05).
