tetracycline and Hyperparathyroidism--Secondary

Topics: Adrenal Cortex Hormones; Antacids; Antibiotics, Antineoplastic; Anticoagulants; Anticonvulsants; Bone and Bones; Bone Diseases; Cadmium; Cathartics; Chronic Disease; Dactinomycin; Diuretics; Drug-Related Side Effects and Adverse Reactions; Fluorides; Humans; Hyperparathyroidism, Secondary; Iron; Lead; Methotrexate; Plicamycin; Radium; Tetracycline; Vitamin A; Vitamin D

In order to gain insight into the mechanisms underlying the dynamic changes in bone metabolism and bone quality after parathyroidectomy (PTX) in secondary hyperparathyroid patients with high levels of parathyroid hormone (PTH), we performed bone histomorphometric analysis with tetracycline labeling in iliac bone biopsy specimens taken before and after PTX, with special attention paid to osteocytes. At 2 to 4 weeks after PTX, PTH concentrations decreased markedly with evident reductions in bone turnover markers. Histomorphometry revealed that at 2 to 4 weeks following PTX, the osteoclast surface decreased to nearly 0%, with a substantial increase in osteoid volume and a reduction in fibrosis volume. Labeling with tetracycline was observed not only at the mineralization front on the bone surface but also around the osteocyte lacunar walls and canaliculi within both the basic multicellular units (BMUs) and bone structural units (BSUs), suggesting that mineralization was taking place along the lacunocanalicular system after PTX. The tetracycline-labeled area was much greater in the BSUs than in the BMUs and at the mineralization front, and the tetracycline labeling in the BSUs was markedly increased after PTX compared with that in the low- and high-PTH control groups without PTX. The osteocyte number was decreased significantly after PTX, concomitant with an increase in the number of empty lacunae and a reduction of lacunar volume. Thus the increased osteocyte death and mineralization around the lacunocanalicular system in association with a rapid decline in PTH may underlie the changes in bone metabolism and quality that occur following PTX.

Topics: Adult; Aged; Bone and Bones; Bone Remodeling; Calcification, Physiologic; Cell Count; Cell Death; Female; Humans; Hyperparathyroidism, Secondary; Male; Middle Aged; Osteocytes; Parathyroidectomy; Tetracycline

Alkaline phosphatase (ALP) activity is a new histomorphometric index of the extent of osteoblastic surfaces involved in mineralization. To assess its validity in the evaluation of bone formation, we carried out a comparative study between histomorphometric values obtained on the basis of the extent of tetracycline labeling and of the length of ALP-positive endosteal surfaces. The following variables were compared (indicated by ALP when based on the extent of ALP positivity): trabecular mineralizing surface (MS/BS vs. ALP.S/BS); osteoid mineralizing surface (MS/OS vs. ALP.S/OS); bone formation rate (BFR/BS vs. ALP.BFR/BS); and adjusted appositional rate (Aj.AR vs. ALP.Aj.AR). Bone biopsies from 39 patients with chronic renal failure and different types of renal osteodystrophy were considered (48 +/- 12 years of age; 19 men and 20 women). Patients were double labeled with tetracycline and biopsies were embedded in glycol-methacrylate at +4 degrees C. Patients showed various types of renal osteodystrophy and were assigned to different groups of pathologies. Although it differed in incidence according to the different groups, ALP activity was found in typical plump osteoblasts bordering osteoid seams and in flat cells, either in contact with osteoid or along the quiescent surfaces of bone in continuity with it. Tetracycline codistributed with all these features to variable extents, according to groups. In all patients, however, ALP.S/BS and ALP.S/OS respectively exceeded MS/BS and MS/OS. In consequence of this, ALP.BFR/BS and ALP.Aj.AR were greater than BFR/BS and Aj.AR, respectively. For each of the variable considered, differences among groups of patients with different types of renal osteodystrophy were highly significant. Good correlations were found between the variables measured with the two methods.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Adult; Alkaline Phosphatase; Biopsy; Bone Development; Calcification, Physiologic; Calcinosis; Calcium; Chronic Kidney Disease-Mineral and Bone Disorder; Female; Histocytochemistry; Humans; Hyperparathyroidism, Secondary; Ilium; Image Processing, Computer-Assisted; Kidney Failure, Chronic; Male; Middle Aged; Osteoblasts; Osteocalcin; Osteomalacia; Parathyroid Hormone; Phosphates; Tetracycline

Topics: Animals; Bone Development; Bone Matrix; Bone Resorption; Calcium; Hyperparathyroidism, Secondary; Hypocalcemia; Male; Parathyroid Glands; Phosphorus; Rats; Tetracycline

Topics: Animals; Autoradiography; Bone Resorption; Calcitonin; Calcium Isotopes; Cats; Epiphyses; Femur; Gelatin; Hyperparathyroidism, Secondary; Hypocalcemia; Microradiography; Nephrectomy; Osteogenesis; Parathyroid Glands; Phosphates; Swine; Tetracycline; Thyroidectomy

Topics: Adolescent; Adult; Biopsy; Bone Regeneration; Bone Resorption; Chronic Kidney Disease-Mineral and Bone Disorder; Female; Haversian System; Humans; Hyperparathyroidism; Hyperparathyroidism, Secondary; Kidney Failure, Chronic; Male; Middle Aged; Osteoclasts; Renal Dialysis; Tetracycline