Objective: To study the role of calpain in the mechanism of oxidative cataract through detecting the level of intracellular free Ca2+, the expression and proteolytic activity of calpain in the lens epithelial cells (...Objective: To study the role of calpain in the mechanism of oxidative cataract through detecting the level of intracellular free Ca2+, the expression and proteolytic activity of calpain in the lens epithelial cells (LECs) of H2O2-induced cataract. Methods: Rat lenses were cultured in vitro and cataract was induced by H2O2. The level of intracellular free Ca2+ was measured by fluorescence determination with fura-2/AM. The expression of m-calpain protein in LECs was detected with immunohistochemical method. The proteolytic activity in LECs was measured using a fluorogenic synthetic substrate. Results: There were significant differences of the level of intracellular free Ca2+ (P=0.001, 0.000, 0.000), the expression of m-calpain (P=0.001, 0.000, 0.000) and the proteolytic activity of calpain (P=0.001, 0.000, 0.000) between H2O2-induced and control group at 6, 12 and 24 h, respectively. Conclusions: H2O2 can increase intracellular free Ca2+, then enhance the expression and proteolytic activity of calpain which may play a role in the mechanism of oxidative cataract of rat.展开更多
Fine structure of the hypobranchial gland of Haliotis diversicolor has been studied by light and electron microscopy. The results showed that the gland is folded pleats organ, which is highly glandular area of the epi...Fine structure of the hypobranchial gland of Haliotis diversicolor has been studied by light and electron microscopy. The results showed that the gland is folded pleats organ, which is highly glandular area of the epidermal lining the roof of the mantle cavity. Two such glandular areas, one on each side of the rectum, occur in H. diversicolor. Left one is much larger than fight one. By light microscope, on H-E stained section, four cell types can be divided: cells with weak basophilic fibrillar elements; with acidophilic granular substance; with strong basophiIic fibrillar elements and ciliated ceils. In the basal lamina region under the gland epithelium, there are a few connective tissues. Surface view of the gland could be seen by scanning electron microscope, there are cilia and different kinds of secretions distributed. By transmission electron microscope, supporting cells, sensory cells and seven types gland cells were observed to form the glandular epithelium. Cells are rich in rough endoplasmic reticulum, smooth muscle fiber and nerve endings were found beneath glandular epithelium, between basal lamina.展开更多
文摘Objective: To study the role of calpain in the mechanism of oxidative cataract through detecting the level of intracellular free Ca2+, the expression and proteolytic activity of calpain in the lens epithelial cells (LECs) of H2O2-induced cataract. Methods: Rat lenses were cultured in vitro and cataract was induced by H2O2. The level of intracellular free Ca2+ was measured by fluorescence determination with fura-2/AM. The expression of m-calpain protein in LECs was detected with immunohistochemical method. The proteolytic activity in LECs was measured using a fluorogenic synthetic substrate. Results: There were significant differences of the level of intracellular free Ca2+ (P=0.001, 0.000, 0.000), the expression of m-calpain (P=0.001, 0.000, 0.000) and the proteolytic activity of calpain (P=0.001, 0.000, 0.000) between H2O2-induced and control group at 6, 12 and 24 h, respectively. Conclusions: H2O2 can increase intracellular free Ca2+, then enhance the expression and proteolytic activity of calpain which may play a role in the mechanism of oxidative cataract of rat.
基金Acknowledgments: This study was founded by Natural Science Foundation of Guangdong (No. 032248) and Large Instrument Using Fund of South China Agricultural University ( No. 2007Y002 ) .
文摘Fine structure of the hypobranchial gland of Haliotis diversicolor has been studied by light and electron microscopy. The results showed that the gland is folded pleats organ, which is highly glandular area of the epidermal lining the roof of the mantle cavity. Two such glandular areas, one on each side of the rectum, occur in H. diversicolor. Left one is much larger than fight one. By light microscope, on H-E stained section, four cell types can be divided: cells with weak basophilic fibrillar elements; with acidophilic granular substance; with strong basophiIic fibrillar elements and ciliated ceils. In the basal lamina region under the gland epithelium, there are a few connective tissues. Surface view of the gland could be seen by scanning electron microscope, there are cilia and different kinds of secretions distributed. By transmission electron microscope, supporting cells, sensory cells and seven types gland cells were observed to form the glandular epithelium. Cells are rich in rough endoplasmic reticulum, smooth muscle fiber and nerve endings were found beneath glandular epithelium, between basal lamina.