muramidase and Lead-Poisoning

The adverse and beneficial effects of metals have occupied a great concern in many branches of biology for centuries, but their biochemical roles have been studied systematically only in the last four decades. Almost all the metals, especially those of high toxicity, bind readily to mercapto groups, and these are frequently important in enzyme systems. Furthermore, a large number of in vitro and in vivo studies have shown that toxic metals can replace essential metals in many of their metalloenzymes, with resultant changes in activity. Metals also bind to protein, phospholipid and nucleic acid, and have been shown to effect a change in the conformation of enzymes required for normal function, or to uncouple oxidative phosphorylation. This review, of necessity brief, will focus on the biochemical and enzymatic effects of metals, emphasizing meanings available to occupational medicine. The present knowledge on enzymatic toxicology of metals can provide for access to three main problems. These include an exposure evaluation, a health injury evaluation and a pathogenic understanding of workers exposed to metals. In this article, these problems are discussed in general, and the recent developments made in the enzymatic toxicology of cadmium and lead are presented with pertinent literatures.

Topics: Alanine Transaminase; Alkaline Phosphatase; Animals; Aspartate Aminotransferases; Cadmium; Cadmium Poisoning; Environmental Exposure; Humans; Kidney Diseases; Lead Poisoning; Metals; Muramidase; Occupational Diseases; Porphobilinogen Synthase; Rabbits; Rats

Groups of female rats were exposed for prolonged periods to different lead concentrations in drinking water; in one group was also added to the drinking water, in the amniotic fluid of exposed females greatly reduced lysozyme values were found, as compared with controls. Concurrent Zn administration considerably reduced the effect of lead. Long-term exposure to low concentrations of lead caused a greater drop of lysozyme levels in amniotic fluid than that found in previous experiments after short-term exposure to higher lead concentration.

Topics: Amniotic Fluid; Animals; Female; Lead Poisoning; Muramidase; Pregnancy; Pregnancy Complications; Rats; Rats, Inbred Strains

Topics: Blood; Environmental Exposure; Humans; Lead Poisoning; Male; Metallurgy; Mouth Mucosa; Muramidase; Occupational Diseases; Phagocytosis; Saliva; Skin; USSR

Topics: Anti-Infective Agents, Local; Blood; Cholesterol; Humans; Lead Poisoning; Muramidase; Occupational Diseases; Research