An experimental study on silver in the nervous system and on aspects of its general cellular toxicity. Rungby J Dan Med Bull 1990 Oct 37:442-9
Abstract Exposure of foetal and adult rats to silver results in a long-lasting deposition of the metal in many structures of the nervous system. A brief anatomical description of the localization of silver deposits as they are visualized by autometallography is provided. The consequences of silver in the nervous system were evaluated by volumetric measurements on developing rat hippocampi which showed that silver induced a decrease in the total volume of hippocampal pyramidal cells. The toxicity of silver at the cellular level was studied in a test-system of cultured macrophages. High doses of silver caused coagulation necrosis, whereas lower concentrations resulted in a cytotoxic and possibly a cytostatic effect without affecting cell structure. The processing of silver which resulted in lysosomal accumulations was affected by the metal itself in a dose-dependent fashion (autointerference). Other basic macrophage functions (protein-production, phagocytosis, migration) were not affected by silver at concentrations which did not cause acute cell death. Biochemically, silver causes an increase in lipid peroxidation, which was evident only in liver tissue. Coagulation necrosis and, to some extent, long-term effects on cell viability could be reversed by inorganic selenium, which was tested as a detoxicant. On the other hand, pre-exposure of animals to selenium greatly enhanced the silver-induced lipid peroxidation. Furthermore, the co-exposure to silver and nickel resulted in a synergistically increased lipid peroxidation. ******************************************** Toxicology Volume 186, Issues 1-2 , 15 April 2003, Pages 151-157 Accumulation of silver from drinking water into cerebellum and musculus soleus in mice Kai H. O. Pelkonena, Helvi Heinonen-Tanski, , b and Osmo O. P. Hänninena a Department of Physiology, University of Kuopio, POB 1627, FIN 70211, Kuopio, Finland b Department of Environmental Sciences, University of Kuopio, POB 1627, FIN 70211, Kuopio, Finland Received 9 August 2002; revised 11 December 2002; accepted 11 December 2002. Abstract In spite of the general toxicity, ecotoxicity and sparsely known metabolism of silver, WHO allows silver ions (Ag) up to 0.1 mg/l in drinking water disinfection. In order to determine the accumulation and distribution of silver in a mammalian body, mice were given for 1 and 2 weeks drinking water containing a 3-fold lower concentration, namely 0.03 mg/l silver ions as silver nitrate labelled with 110mAg. The silver concentrations in different tissues were analysed by gamma radioactivity. The saturation of tissues with silver seems to occur quickly, as there were no statistical differences between silver contents of mice tissues in spite of the study design that mice were administered silver for 1 or 2 weeks. The highest concentrations were found in musculus soleus (m. soleus), cerebellum, spleen, duodenum, and myocardial muscle in the rank order. Concentrations of silver in musculus gastrocnemius (m. gastrocnemius) were found to correlate negatively with cerebrum and positively with blood and kidneys. The accumulation of silver into organs and tissues important in motor functions may be of relevance especially in emergency and catastrophe situations in which accurate motor functions may be critical. A re-evaluation of the present recommendations on the use of silver salts for disinfection of drinking water might be necessary. -- The silver-list is a moderated forum for discussion of colloidal silver. Instructions for unsubscribing may be found at: http://silverlist.org To post, address your message to: silver-list@eskimo.com Silver-list archive: http://escribe.com/health/thesilverlist/index.html List maintainer: Mike Devour <mdev...@eskimo.com>
