Ultrastructural Changes in the Mantle of the Equilateral Venus, Gomphina veneriformis (Bivalvia: Veneridae) Exposed to TBTCl

Abstract

Equilateral venus, Gomphina veneriformis exposed to tribultyltin chloride (TBTCl) for 36 weeks was showed ultrastructural changes of the mantle. The fine mantle had 4-folds and its epidermal layer consisted of simple columnar epithelial cells and ciliated cells and secretory cells. Inner and outer epidermal layer covered connective tissue. The mantle exposed to TBTCl at 12 weeks was decreased cilia in the inner epidermal layer, and observed extension of the hemolymph sinus and destruction of the septum. At 20 weeks, it revealed vacuole formation and pycnosis in the cytoplasm, and scattered muscular fiber. After 28 weeks of exposure, the mantle revealed partially degenerative changes in the epidermal layer. In the ciliated cells, basal body was isolated from the cilia and rootlet complex and basal foot were scattered. The sarcolemma had debris fiber. At 36 weeks, it observed degenerative cells that it revealed disappearance of the cilia, atrophic nucleus, poorly membrane and destruction of the cresternae in the mitochondria, and increasing heterophagosome. The outer epithelial cell had necrotic nuclus, numeous lysosome and disappearance of the microvilli. Therefore, results of this study suggested that chronical TBTCl exposure in the Gomphina veneriformis induced the disorders of shell growth and physiological function with histopathological changes of the mantle.

Gomphina (Macridiscus) veneriformis (Lamark, 1818) (Bivalvia: Veneridae) in the East Sea of Korea

“…To date, regarding Gomphina spp., there have been several studies on aspects of reproduction, including the spawning season, artifitial fertilization and egg development (Lee, 1976), goanadal development and reproductive cycle (Lee et al, 1999), and germ cells and the accessory cells during spermatogenesis (Chung et al., 2010), and on aspect of ecology, including culture (Lee, 1976) and age and growth (Hwang and Hwang, 1981;Jung, 2011), and on aspects of toxicology and physiology (Pank and Lee, 2008Lee, , 2010Lee, , 2011. Although there are some reproductive ecological studies, there are still gaps in our knowledge on reproductive ecology associated with the gametogenic cycle and the spawning season.…”