Fig. 4

Ultrastructure of tentacle nerves and blood vessel of Owenia borealis (TEM). A Epithelium of aboral side: different types of cells. Two supportive cells are shown by different colors; perikaryon is shown in yellow. B The base of epithelium of aboral side: two types of glial cells are shown by red and blue. Vesicles in glial cell are indicated by concaved arrowheads. C Epithelium of oral side with perikaryon (yellow) and glial cell (red). Vesicles in perikaryon are indicated by concaved arrowheads. D Myoepithelial cells (green) of coelomic lining, which form the wall of blood vessel. Adherence junctions between cells are indicated by straight arrowheads. Abbreviations: bb – basal body; bv – blood vessel; ci – cilium; ecm – extracellular matrix; eas – epithelium of aboral side; eos – epithelium of oral side; if – intermediate filaments; mf – myofilaments; n – nucleus; nb – neurite bundle; pc – peritoneal cells; tcm – tentacle transverse muscles; tlm – tentacle longitudinal muscles