The multifunctional muscle cell in anthozoans is called an epitheliomuscular cell
. It is located in the ectodermal layer and also in the endodermal layer of the body wall.
The common form of muscle cells that make up epidermal or gastrodermal muscle sheets is the epitheliomuscular cell (Chapman, 1974).
Chapman (1978) described the tentacle musculature of the Tripedalia cystophora cubopolyp as smooth longitudinal epitheliomuscular cells but noted the presence of striated myofibrils near the distal tip of the tentacles.
This degree of contractility likely would create problems with wrinkling if the musculature were composed of epitheliomuscular cells, because compression of the epithelial component would resist the shortening of the muscular component.
Biochemical studies have also indicated the presence of a receptor in membrane fractions of hydra that binds to the NMDA channel blocker, MK-801 (Pierobon et al., 2004a), and immunocytochemical studies provided evidence that NMDA receptors exist on the surface of nerve cells, nematocytes, myonemes of epitheliomuscular cells, and interstitial stem cells (Scappaticci et al., 2004).
Although the impulses form a heterogeneous group (i.e., large variability in amplitude and duration), they must nonetheless be considered to arise from either nerve or epithelial cells (including epitheliomuscular cells, nematocytes, and stem cells), or both.
Whereas control animals that were hybridized with actin antisense probes labeled strongly in the mesenteries, which are rich in epitheliomuscular cells
The movement of the fluid in gastrovascular systems of cnidarians could be driven by contractions of the epitheliomuscular cells
(Van Winkle and Blackstone, 1997) or contractile vacuoles (Schierwater et al., 1992), or by the activity of cilia.