Impaired growth, delayed ossification, and reduced osteoclastic activity in the growth plate of calcium-supplemented rats with renal failure.

Linear growth is reduced in prepubertal children with adynamic renal osteodystrophy, suggesting that the proliferation and/or differentiation of epiphyseal growth plate chondrocytes is abnormal in this disorder. To examine this issue, in situ hybridization and histochemistry were used to measure selected markers of endochondral bone formation and bone resorption in the proximal tibia of subtotally nephrectomized rats fed a high calcium diet to induce biochemical changes consistent with adynamic osteodystrophy. Blood ionized calcium concentrations were higher and serum PTH levels were lower in nephrectomized, calcium-supplemented rats than in either intact or nephrectomized control animals.

Growth of long bones in renal failure: roles of hyperparathyroidism, growth hormone and calcitriol.

Background: The treatment of secondary hyperparathyroidism (2 degrees HPT) associated with chronic renal failure adversely affects skeletal growth.

Methods: We assessed epiphyseal growth plate morphology by quantitative histology and measured mRNA levels for selected markers of chondrocyte proliferation and differentiation by in situ hybridization in the growth plate cartilage of subtotally nephrectomized rats with either mild or advanced 2 degrees HPT.

Results: The width of the growth plate cartilage in the proximal tibia and mRNA levels for PTH/PTHrP receptor were unchanged in rats with mild 2 degrees HPT, however, they were markedly less in nephrectomized rats with advanced 2 degrees HPT than in intact controls.

Glycosylation of hemoglobin S by reducing sugars and its effect on gelation.

The binding of various reducing mono- and disaccharides to hemoglobin S has been measured both before and after treatment of the sugar-protein adducts with NaBH4. Incubation of 0.3 M solutions of D-glucose, D-galactose, D-maltose, and lactose, with 2% hemoglobin for 2 h at 37 degrees C, pH 7.