Skeletal changes and growth in experimental uremia.
Longitudinal growth; bone and growth zone histology; growth cartilage and bone mineralization (tetracycline technique); bone Ca content (neutron activation analysis); bone radiology; serum and urine chemistry; urinary cAMP and serum 25-OH-vitamin D3 were studied in a long-term model of experimental uremia in the rat. Uremia was induced by two-stage subtotal nephrectomy with irradiation of the remaining parenchyma. Ccr in the experimental group was 113 +/- 5.8 micron1/min X 100 g (19.8% of controls) and serum creatinine 1.67 +/- 0.04 mg% (5.1 X control value). Uremic animals were pair-fed with sham-operated controls. In the proximal tibia delayed transformation of cartilage into primary spongiosa with appearance of chondro-osteoid and delayed transformation of primary spongiosa into secondary spongiosa was observed (rickets). Increased amounts of osteoid were present although 25-OH-vitamin D3-levels were high. There were only modest signs of secondary hyperparathyroidism (osteoclast counts; urinary cAMP). In spite of the presence of bone disease, longitudinal growth was not reduced in uremic animals as compared with pair-fed sham-operated animals, but was significantly reduced as compared with ad lib fed control animals. In contrast, weight gain was significantly diminished in uremic animals as compared with pair-fed sham-operated control animals. It is concluded that diminished intake of food is the major determinant of growth retardation in preterminal experimental renal failure.
D000469:Alkaline Phosphatase / Q000097:blood; D000818:Animals; D001835:Body Weight; D001842:Bone and Bones / Q000473:pathology / Q000503:physiopathology*; D003404:Creatinine / Q000097:blood; D000242:Cyclic AMP / Q000652:urine; D004195:Disease Models, Animal; D004573:Electrolytes / Q000097:blood / Q000652:urine; D006128:Growth; D008297:Male; D051381:Rats; D014508:Urea / Q000097:blood; D014511:Uremia / Q000473:pathology / Q000503:physiopathology*
D004573:Electrolytes; D014508:Urea; D003404:Creatinine; D000242:Cyclic AMP; D000469:Alkaline Phosphatase