Mitochondrial inner membrane potential and ROS • Tat1–86, Tat1–72 • gp120 No Morphine ↑ ΔΨm instability and oxidative stress ↑ with Tat + morphine, ↑ neuroprotection with allopregnanolone Human, primary neurons ; mouse, striatal medium spiny neurons; mouse, striatal medium spiny neurons, SH-SY5Y neuroblastoma cells (Turchan-Cholewo et al. 2006; Paris et al. 2020)