Fig. 5

Maraviroc reduces Tat-mediated increases in [Ca²⁺]_i. Intracellular calcium levels were assessed in neuron-glia co-cultures by ratiometric imaging of Fura-2. A series of images were taken every 15 min for 1 h to track the response of individual neurons. Initial [Ca²⁺]_i measurements were taken prior to any treatment at the 0-min time point. Tat and/or morphine treatments were applied 10 min prior to the second reading (marked by arrow). There were significant effects for both time (p = 0.001) and treatment (p = 0.009) when assessed by repeated measures ANOVA. Treatment with Tat or Tat + morphine (marked by asterisk) led to significant increases in [Ca²⁺]_i, as indicated by increased F340/F380 ratios. Pre-treatment with maraviroc blocked the Tat + morphine-induced increase (p = 0.008; Duncan’s post hoc test) as well as the Tat-mediated response (p = 0.054). Morphine and maraviroc alone did not significantly alter [Ca²⁺]_i. Results are presented as percent of the control F340/F380 ratios for each concurrent time point (n = 3 independent experiments)