Two-photon image of a rat cerebellum stained for the IP3 receptor (green), GFAP (red) and cell nuclei (blue) was acquired using a Bio-Rad multiphoton imaging system. Image courtesy of T. Deerinck, J. Bouwer, S. Chow, and M. Ellisman, NCMIR, UCSD, USA.

The image is a mid-sagittal section of whole rat cerebellum stained for IP3 receptor (concentrated in Purkinje cell neurons, FITC, green), GFAP (glial fibrillary acidic protein that is present in glial cells, rhodamine, red), and cell nuclei (stained blue with the DNA binding dye Hoechst 33342). 2-photon excitation at 800 nm.

The cover image represents only 1% of the whole image, which is a composite of 40 images in x, by 36 images in y, by 10 images in z in 3 channels. The images were acquired over approximately an 8-hour period. This method allows one to acquire near diffraction limited resolution of centimeter-plus sized specimens.