title: The complexity of the visual cells and visual pathways of the sturgeon.
abstract: The visual cells in the retinae of the sturgeon were studied by scanning electron microscopy and transmission electron microscopy. Our investigations revealed the presence of rods, two types of single cones, one type of double cone (two nonidentical cone components adhered together), and one type of twin cone (two identical cone components adhered together). In some of the cones, large glycogen bodies were present in the inner segments and all cones contained oil droplets. Such cone morphology was very similar to that described in the retinae of higher vertebrates, for example the chicken. DiI tracing of retinofugal pathways following uniocular injection demonstrated their bilateral localization and extensive termination in the diencephalon and mesencephalon of both sides. Fibers also crossed over from one side to another through commissures, including the posterior commissure. The complexity of the pathway surpassed that of the teleosts and further indicated the evolutionary importance of this fish.
authors.affiliation: Department of Anatomy and Institute of Cell Biology, Medical School of Zhejiang University, China.
authors.forename: Marong
authors.initials: M
authors.lastname: Fang
authors.forename: Jicheng
authors.initials: J
authors.lastname: Li
authors.forename: W H
authors.initials: WH
authors.lastname: Kwong
authors.forename: P
authors.initials: P
authors.lastname: Kindler
authors.forename: Gang
authors.initials: G
authors.lastname: Lu
authors.forename: Sen Mun
authors.initials: SM
authors.lastname: Wai
authors.forename: David T
authors.initials: DT
authors.lastname: Yew
mesh_terms: D000818:Animals; D002232:Carbocyanines / Q000378:metabolism; D004027:Diencephalon / Q000648:ultrastructure; D005399:Fishes / Q000033:anatomy & histology*; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D017949:Retinal Cone Photoreceptor Cells / Q000648:ultrastructure*; D017948:Retinal Rod Photoreceptor Cells / Q000648:ultrastructure*; D013194:Staining and Labeling; D014617:Vacuoles / Q000648:ultrastructure; D014795:Visual Pathways / Q000601:surgery*
chemical_list: C035005:3,3'-dihexadecylindocarbocyanine; D002232:Carbocyanines