Lead and Lead Poisoning from Antiquity to Modern Times

Author Institution: Department of Physiology, Ohio State UniversityLead, because of its low melting point, was one of the first metals used by man. It was probably isolated soon after the ancients discovered the use of fire. Archeological discoveries indicate the presence of lead objects and pigments during the early Bronze Age. In ancient Egyptian and Greco-Roman times metallic lead was produced as a by-product of silver mining. Extensive evidence of ancient mining and smelting exists in both the Orient and Mediterranean regions. Although generally thought of as a disease of the Industrial Revolution, lead poisoning has been documented for 6,000 years. As early as the 4th century BCE, Hippocrates accurately described the symptoms of lead poisoning. However, it was not until the 19th and 20th centuries that lead as an occupational health factor became a public issue. During Greco-Roman and Medieval times sapa, a sweet lead acetate syrup, was added to both wines and food. This resulted in widespread lead intoxication among the affluent and has been suggested as a probable reason for the fall of the Roman Empire. Fortified wines from Spain and Portugal, rum from the Colonies, and cider precipitated epidemics of lead poisoning. Since 1970 the National Institutes of Occupational Safety and Health have monitored environmental lead and significantly reduced lead exposure in air, water, and food

Respiratory Activity of Isolated Chondrocytes with a Miniaturized Oxygen Electrade System

Author Institution: Department of Physiology, Ohio State University ; Department of Surgery, Ohio State UniversityA technique for the isolation of chondrocytes from the articular cartilage of rabbits was modified and improved to yield 5 to 20 x 106 viable cells per preparation. A YSI Model 5331 O2 sensor was modified so that it could rapidly respond in as little as 1 ml of medium. Mean oxygen uptake of cell samples showed that chondrocytes obtained from mature rabbits (1.33 /J! O2/107 cells/hr) had a higher oxidative activity than chondrocytes from immature rabbits (0.8 (A O2/107 cells/hr). Elevation of the incubation temperature from 25 °C to 35 °C increased the chondrocyte oxygen uptake approximately 20% but incubation at 37 °C tended to decrease oxygen uptake. It is evident that articular chondrocyte cells have a real, but fairly low, temperature sensitive oxidative metabolism

Controlled Phenylhydrazine-Induced Reticulocytosis in the Rat

Author Institution: Department of Physiology, Ohio State University, College of Medicine, Columbus, Ohio 43210The pattern of development of phenylhydrazine-induced rat reticulocytosis was studied over a period of nine days. Intraperitoneal injections of phenylhydrazine (4 mg/100 gm) every other day caused a fall in hematocrit which leveled off at 60% of normal by the fifth day. Increased erythropoiesis was indicated by a three-fold increase in the number of circulating reituclocytes after the first three injections. The immediate response was the release of stored mature reticulocytes from the bone marrow. As the anemia progressed, more and more young reticulocytes appeared until 70 to 85% of the red cells in the peripheral circulation were reticulocytes and 20% of these were juvenile forms