Figure 3. Increasing two-photon (2P) excitation wavelength decreased Hoechst 33342 nuclear fluorescence intensity and increased autofluorescence (AF) intensity. Two tissue sections from the same donor were fixed and incubated without (A, C, E) or with Alexa-568-conjugated phalloidin (B, D, F) and imaged. Emission from the uveal meshwork following 2P excitation at 800 nm (A, B), 850 nm (C, D), and 900 nm (E, F) was captured through a green filter (500–550 nm). Region-of-interest (ROI) analysis of AF (green) and Hoechst 33342 nuclear fluorescence (blue) are illustrated. Bar=25 μm.