Fig. 6

Exogenous BDNF protects against Tat + morphine treatment. Wild-type, mixed glial-neuronal co-cultures were treated with BDNF in conjunction with Tat or Tat + morphine co-treatment (represented by dotted survival curves). Tat alone was toxic compared to no treatment (*p < 0.05), and Tat + morphine co-treatment was significantly more toxic than Tat treatment alone (**p < 0.0001). BDNF applied for 72 h was entirely protective against Tat and morphine co-exposure, reducing toxicity to control levels (n = 4). BDNF was partially protective against Tat alone. Survival of neurons treated with Tat + BDNF was not significantly different from either controls or cultures treated with Tat alone (#) (n = 4)