Figure 1.

In vivo assessment of the permeability of the BBB to fluorescent compounds. Zebrafish larvae (casper line) at 7–8 dpf were immersed in egg water containing 1 μM of an ID or fluorescein for 1 h. In vivo fluorescence imaging of the zebrafish brain was performed using fluorescence microscopes. A: Schematic diagram showing the region observed using the fluorescence microscopes. B-H: In vivo fluorescence imaging of zebrafish larvae stained with ID possessing a rhodanine ring with an acetic acid group (ZMB996, ZMC213, and ZMJ018, B, C and D, respectively), with fluorescein (E), and with ID possessing a rhodanine ring with a propanoic acid group (ZMC808, ZMB740, and ZMB034, F, G and H, respectively). The OT was clearly visualized in zebrafish stained with IDs possessing a rhodanine moiety with a propanoic acid group. Scale bar: 100 μm. OT, optic tectum; CBV, cerebral blood vessel.