fig. 8.
Mammalian CA1 hippocampal neurons imaged in vivo with two-photon fluorescence microendoscopy. The endoscope probe is positioned atop the alveus in CA1. A: Di-I labeled dendrites in CA1 s. oriens of a live rat. The endoscope probe had a 1,000-μm diam, 0.48 NA, and a 130-μm WD. The image acquisition time was 0.77 s. B–F: in vivo two-photon microendoscopy images of fluorescent cell bodies, basal dendrites, and apical dendrites in CA1 s. pyramidale, s. oriens, and s. radiatum, respectively, in anesthetized YFP-H mice that express YFP in a subset of hippocampal pyramidal neurons (Feng et al. 2000). B: in vivo image of CA1 pyramidal cell basal dendrites in s. oriens. The endoscope probe had a 500-μm diam, 0.47 NA, and a 130-μm WD. Image acquisition time was 0.55 s. C: an image of over 25 pyramidal cell bodies taken with a 1,000-μm-diam endoscope with 1,040-μm WD and 0.38 NA. Image acquisition time was 0.38 s. D: in vivo image of pyramidal cell bodies using the same endoscope probe as in C but at higher digital magnification and with an acquisition time of 0.55 s. E: image of pyramidal cell bodies acquired in vivo with a 500-μm-diam endoscope probe, of 100-μm working distance and 0.47 NA. Image acquisition time was 0.55 s. F: two-photon image of larger dendrites in s. radiatum, ventral but proximal to s. pyramidale. The endoscope probe and acquisition time were identical to that used in E, but the digital magnification was increased. All scale bars are 10 μm.