Figure 6.

BBB permeability is increased within thalamic nuclei following exposure to nicotine-free e-cigarette products. NaF (green, A, D, G, J) and TMR-dextran (red, B, E, H, K) tracers for permeability were added to the vascular space shortly before tissue harvest along with Lycopersicon esculentum lectin (LEL) (cyan, O) as a vascular label. Fresh frozen sections were collected to contain the hippocampus, caudate nucleus, thalamus, and parietal cortex. Merged images of both tracers with LEL are shown (C, F, I, L) with boxed regions of room air and EC0% groups (C, F) shown at higher magnification (O). Fluorescent intensity of NaF (M) and TMR-dextran (N) were quantified for individual regions and normalized to fluorescent intensity of respective tracers in serum. Values for each animal are shown as individual points (n = 4–6 mice/group) with group mean and standard error indicated by bars. *, p < 0.05; **, p < 0.01 versus room air. Two-way ANOVAs were applied to NaF [exposure, F(3,70)=8.008, p=0.0001; region, F(3,70)=0.5105, p=0.6763; interaction, F(9,70)=0.5623, p=0.8232] and TMR-dextran [exposure, F(3,72)=8.376, p<0.0001; region, F(3,72)=0.2591, p=0.8546; interaction, F(9,72)=0.7451, p=0.6665]. Scale bar, 500 μm.