Ultrastructure of transrectal coelomoducts in the sea cucumber Parastichopus californicus (Echinodermata, Holothuroida)
Date
1990
Journal Title
Journal ISSN
Volume Title
Publisher
Springer-Verlag
Abstract
The perivisceral coelom of the sea cucumber Parastichopus
californicus is connected to the lumen of the hindgut
by as many as 200 short transrectal ducts. Each duct
is lined by a pseudostratified epithelium composed of: (i)
monociliated, tonofilament-containing cells, (ii) myoepithelial
cells, (iii) bundles of neurites, and (iv) granule-containing
cells. In most places the lumen of each duct is lined
by the monociliated, tonofilament-containing cells. The
myoepithelial cells are predominantly basal in position and
circular in orientation, but some border the lumen and parallel
the long axis of the duct. The epithelium of a duct
consists of the same types of cells as occur in the peritoneum
covering the rectum and differs markedly from the nonciliated,
cuticularized epithelium that lines the lumen of the
rectum. Based on ultrastructural characteristics, the transrectal
ducts represent evaginations of the peritoneum overlying
the rectum and are thus "coelomoducts" sensu Goodrich.
The possibility is discussed that perivisceral coelomoducts
of holothuroids function in regulating coelomic volumes.
Description
Copyright held by publisher
Keywords
Biology
Citation
George L. Shinn, Stephen A. Stricker, and Michael J. Cavey "Ultrastructure of transrectal coelomoducts in the sea cucumber Parastichopus californicus (Echinodermata, Holothuroida)" Zoomorphology (1990) 109 : 189-199