The Gastric Shield and the Undrelying Epithelium of Chlamys Farreri:Morphological,Histological and Histochemical Characterizations

The gastric shield and underlying stomach epithelium of Chlymas ffarreri were examined at the light and ultrastructural levels.The results showed that the gastric shield consisted of two different size lobes joined together by a narrow middle piece,the thicker lobe was shaped like a funnel,but unclosed at the lateral side;the other lobe was irregularly triangular-shaped.The transverse section of the thicker lobe was obviously laminated and gradually decreased in thickness from the peak to the margins of the shield.The underlying epithelium bore numerous about 3μm diameter spherical processes formed by the apical plasmalemma of the epithelial cells becoming blunt pseudopodia.Microvilli and some interspersed cilia were present in the areas among the spherical processes regions where only microvilli existed.Rough endoplasmic reticulum,Golgi apparatus,different-sized electron-dense secretory granules and electron-lucent vacuoles as well las abundant mitochondria were present in the underlying epithelial cells.Fused droplets of the secretion from the underlying epithelial cells formed the gastric shield.

The gastric shield and the underlying epithelium of<Emphasis Type="Italic">Chlamys farreri</Emphasis>: Morphological,histological and histochemical characterizations

The gastric shield and underlying stomach epithelium ofChlymas farreri were examined at the light and ultrastructural levels. The results showed that the gastric shield consisted of two different size lobes joined together by a narrow middle piece, the thicker lobe was shaped like a funnel, but unclosed at the lateral side; the other lobe was irregularly triangular-shaped. The transverse section of the thicker lobe was obviously laminated and gradually decreased in thickness from the peak to the margins of the shield. The underlying epithelium bore numerous about 3μm diameter spherical processes formed by the apical plasmalemma of the epithelial cells becoming blunt pseudopodia. Microvilli and some interspersed cilia were present in the areas among the spherical processes regions where only microvilli existed. Rough endoplasmic reticulum, Golgi apparatus, different-sized electron-dense secretory granules and electron-lucent vacuoles as well as abundant mitochondria were present in the underlying epithelial cells. Fused droplets of the secretion from the underlying epithelial cells formed the gastric shield. This work was supported by the Natural Science Fund of Shandong Province (Y98D14062).