Features of the clear zone of odontoclasts in the Chinook salmon (Oncorhynchus tshawytscha)

Abstract

This study aims to clarify the features of the clear zone of odontoclasts on shedding teeth of a teleost fish, Chinook salmon, Oncorhynchus tshawytscha (Walbaum), using a light microscope to determine the orientation between a cell body and a resorptive lacuna, followed by transmission electron microscopy (TEM).Ultrathin sections of LR White embedded material were incubated in rabbit anti-actin polyclonal antibody and then were incubated with 15 nm gold-conjugated goat antirabbit IgG. The clear zones of odontoclasts showed a variable structure with electron dense structures on sections, but distinct clear zones were not always seen on odontoclasts. In odontoclasts sectioned in the direction perpendicularly to the surface of a resorptive lacuna, some cells showed a wide clear zone, but two types of clear zones were usually observed: a part composed of some cytoplasmic processes and one composed of several complicatedly interwoven processes. Gold particles were localized on the clear zones, especially in electron dense structures; very few gold particles were detected in ruffled borders. These results show that the clear zone of odontoclasts in Chinook salmon contains actin. Our results suggest that the clear zone of an odontoclast in Chinook salmon is not always a wide annular structure.3

A comparative view on mechanisms and functions of skeletal remodelling in teleost fish, with special emphasis on osteoclasts and their function

“…Moreover, there is evidence that some teleosts and other non‐amniotes resorb old teeth completely as an alternative to shedding (Fig. 6B) (Shaw, 1986; Domon et al , 2004, 2006; Witten et al , 2005 a ; Huysseune et al , 2007) perhaps to retain the minerals. In Atlantic salmon, complete tooth resorption occurs in periods of severe mineral deprivation (spawning migration), during which animals also resorb their scales (Shearer, 1992; Persson et al , 1998).…”

An evolutionary view on tooth development and replacement in wild Atlantic salmon (Salmo salar L.)

“…Many decades after the pioneering articles of Parker (1873), Day (1887), De Beer (1937, and Tchernavin (1937Tchernavin ( , 1938, salmonids are increasingly being used in fundamental studies of jaw development and remodeling (Witten and Hall 2001, 2003Gillis et al 2006) as well as in tooth development studies (Domon et al 2004(Domon et al , 2006Fraser et al 2004Fraser et al , 2006aWitten et al 2005;Huysseune and Witten 2006;Jenner and Wills 2007;Huysseune et al 2007). Salmonids are basal protacanthopterygian teleosts.…”

Comparison of expression patterns of cathepsin K and MMP-9 in odontoclasts and osteoclasts in physiological root resorption in the rat molar

“…Either form of root resorption is thought to be followed by trauma in the periodontal ligament (Henry and Weinmann, 1951;Furseth, 1968;Bosshardt and Schroeder, 1994) and therefore might increase the risk of tooth loss due to fracture or extraction. Root resorption lacunae are principally formed by odontoclasts, which develop from the mature monocyte/ macrophage lineage and have cytologic features similar to osteoclasts, including multiple nuclei, ruffl ed borders, clear zones, and tartrate-resistant acid phosphate (TRAP) activity (Domon et al, 2006). It has been proposed that osteoclasts undergoing even more differentiation have a greater number of nuclei with a higher bone resorption activity (Teti et al, 1991;Lees et al, 2001;Manolson et al, 2003).…”