• Korean Journal of Veterinary Research
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• v.29 no.4
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• pp.541-548
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• 1989

The present study was carried out to determine viral antigens and its morphogenesis in the ultrathin frozen and araldite sections of cell cultures infected with ADV by protein A-gold labeling. ADV antigens were labeled with 10nm gold probes, and electron-dense gold particles were mainly present on viral nucleocapsids and viral envelopes. Immunogold labeling in the ultracryosections showed a very low degree of interaction with tissue structures. Immunogold labeling in the ultrathin cryosections can be useful tool for the detection of ADV antigens, and the technique also may provide its great potential for immunocytochemical studies on various virus-host cell Interactions.

• Applied Microscopy
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• v.28 no.4
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• pp.465-475
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• 1998

The cryoprotection, section retrieval and embedding methods were studied for the preservation of ultrastructure of ultracryomicrosections in immunoelectron microscopy. The results obtained were as follows. 1. The cryoprotection of ultrastructure with a mixture containing 1.7 M sucrose and 15% polyvinylpyrrolidone was better than that with 2.3 M sucrose. The stretching caused by surface tension and the electron lucent holes decreased more in the cryosections infused with 2.3 M sucrose than in those with the mixture. 2. The difference between section retrieval solutions in cases of cryoprotection with 2.3 M sucrose was that the destructive .effects such as electron lucent holes and stretching between myofribrils were less in a mixture containing 1% methylcellulose and 2.3 M sucrose than in 2.3 M sucrose. The difference was obscure in the mixture containing 1.7 M sucrose and 15% PVP, but the destructive effects were slightly less in a mixture containing 1% mthylcellulose and 2.3 M sucrose than in 2.3 M sucrose or 1% methylcellulose. 3. The embedding of cryosection on drying with 2% PVA or 2% methylcellulose exhibited some protective effect during observation with transmission electron microscope, but made the ultrastructure more obscure. 4. Mitochondrial membrane and cristae and myofilaments were well delinated in sections infused with 2.3 M sucrose and retrieved with 1% methylcellulose and 2.3 M sucrose. In summary, it is suggested that the cryoprotection with 2.3 M sucrose and section retrieval with a mixture containing 1% methylcellulose and 2.3 M sucrose are good for the ultrastructure of cryosections.

• Applied Microscopy
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• v.30 no.4
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• pp.357-365
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• 2000

Paneth cells have been suggested to contribute to the elimination of excess metals into the intestinal lumen. The purpose of this study wat to investigate the changes of the zinc pools in rats subjected to functional loading with zinc salt by mean of both light and electron microscopical autometallography (AMG). Wistar rats 4 were administrated with zinc chloride (20 mg/kg body weight) intraperitoneally dissolved in 1 ml distilled water. The control group received 1 ml saline IP. After further one hour the animals were transcardially perfused with 0.4% sodium sulphide dissolved in 0.1 M PB fellowed by 3% glutaraldehyde solution for 10 minutes. Pieces of ileum were frozen with solid $CO_2$ and sectioned on a cryostat. The sections $(20{\mu}m)$ were autometallographically developed. Sections selected for EM were reembedded on top of a blank Epon block, from which ultrathin sections (100 nm) were cut. The ultrathin sections were double stained with uranyl acetate (30 min) and lead citrate (5 min), then examined under electron microscope. Studies of comparable sections from control and zinc loaded animals with the AMG selenium method gave quite different results. The control animals demonstrated a weakly positive staining in the cytoplasm of the Paneth cells. In the electron microscope the AMG silver grains were found to be located in the cytoplasm, while the electron dense secretary granules and other cell organelles were void of staining. Few AMG grains were located at the apical surface of the Paneth cells. In sections from zinc loaded rats, the AMG grains were seen in abundance in the lumen of the Lieberkuhn crypts at light microscopic levels. At EM levels the zinc revealing silver grains were located in the cytoplasm as in the controls, but much more AMG grains were shifted into the secretary granules. Furthermore, profound AMG grains were found in the lumen of the crypts and surrounding vessels. And a few grains were seen in the endothelium. The AMG technique demonstrated a pattern of AMG grains in the Paneth cells that strongly suggests a transport of zinc ions through these cells.