title: Serial sectioning for examination of photoreceptor cell architecture by focused ion beam technology.
abstract: Structurally deciphering complex neural networks requires technology with sufficient resolution to allow visualization of single cells and their intimate surrounding connections. Scanning electron microscopy (SEM), coupled with serial ion ablation (SIA) technology, presents a new avenue to study these networks. SIA allows ion ablation to remove nanometer sections of tissue for SEM imaging, resulting in serial section data collection for three-dimensional reconstruction. Here we highlight a method for preparing retinal tissues for imaging of photoreceptors by SIA-SEM technology. We show that this technique can be used to visualize whole rod photoreceptors and the internal disc elements from wild-type (wt) mice. The distance parameters of the discs and photoreceptors are in good agreement with previous work with other methods. Moreover, we show that large planes of retinal tissue can be imaged at high resolution to display the packing of normal rods. Finally, SIA-SEM imaging of retinal tissue from a mouse model (Nrl⁻/⁻) with phenotypic changes akin to the human disease enhanced S-cone syndrome (ESCS) revealed a structural profile of overall photoreceptor ultrastructure and internal elements that accompany this disease. Overall, this work presents a new method to study photoreceptor cells at high structural resolution that has a broad applicability to the visual neuroscience field.
authors: Department of Pharmacology, School of Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH 44106-4965, USA.
authors: Debarshi
authors: D
authors: Mustafi
authors: Amir
authors: A
authors: Avishai
authors: Nanthawan
authors: N
authors: Avishai
authors: Andreas
authors: A
authors: Engel
authors: Arthur
authors: A
authors: Heuer
authors: Krzysztof
authors: K
authors: Palczewski
mesh_terms: D055011:Ablation Techniques / Q000295:instrumentation / Q000379:methods; D000818:Animals; D050976:Basic-Leucine Zipper Transcription Factors / Q000172:deficiency; D005136:Eye Proteins; D021621:Imaging, Three-Dimensional / Q000379:methods; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D008855:Microscopy, Electron, Scanning / Q000379:methods*; D012160:Retina / Q000166:cytology*; D017949:Retinal Cone Photoreceptor Cells / Q000000981:diagnostic imaging*; D017948:Retinal Rod Photoreceptor Cells / Q000648:ultrastructure*; D014463:Ultrasonography
chemical_list: D050976:Basic-Leucine Zipper Transcription Factors; D005136:Eye Proteins; C084884:Nrl protein, mouse