Motion Picture and Electron Microscope Studies on the Embryonic Avian Osteoclast

Hancox, N. M.; Boothroyd, B.

doi:10.1083/jcb.11.3.651

Cited by 94 publications

(15 citation statements)

References 15 publications

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“…About 35 to 40%o of total body collagen is found in bone matrix (26), which in turn constitutes about 30% of the dry weight of bone (27). Osteoclasts may play a role in the process whereby Ca V. parathyroids induce breakdown of bone (28,29); the increase in OHPr excretion presumably results from this breakdown of bone and of insoluble bone collagen. It is not clear, however, whether the collagen of organic matrix is altered directly, or after the salts have been removed.…”

Section: Resultsmentioning

confidence: 99%

Relation between Urinary Hydroxyproline and Parathyroid Function*

Keiser¹,

Gill²,

Sjoerdsma³

et al. 1964

J. Clin. Invest.

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With the exception of small amounts in elastin, all the hydroxyproline (OHPr) in the body is found in collagen. Evidence has been presented that the urinary peptide-bound OHPr reflects the metabolism of collagen (2-5) except when the dietary intake of gelatin or collagen is excessive. Since a major body depot of collagen is the matrix of bone, it might be anticipated that under some conditions the rate of OHPr excretion would furnish an index of the turnover of bone matrix.Parathyroid hormone is known to increase bone resorption (6)(7)(8)(9)(10)(11) received constant diets containing at most 120 g of lean, red meat daily, but no fish, Jello, ice cream, or other gelatin-rich foods. PTE was given intramuscularly at a dosage of 600 U a day for 10 to 12 days. Urine was collected in 24-hour pools under toluene and stored in a cold room at 4°C. Feces were collected in 4-or 6-day pools.2) Four-hour calcium infusion. Calcium glucoheptonate was given to a man (T.W., age, 46 years) and a woman (A.M.S., age, 40 years) with surgically induced hypoparathyroidism, to four normal men (ages, 20 to 42 years), and to five normal women (ages, 18 to 54 years). A.M.S. had been treated with vitamin D and T.W. had not been treated. All these subjects were fed a constant, liquid diet to give a daily intake of 350 mg of calcium (Ca), 980 mg of phosphorus (P), and less than 10 mg of OHPr in the form of protein. The diet was given in five equal feedings daily for 4 days. On day 3 of the diet, Ca, at a dosage of 15 mg per kg, as glucoheptonate in 0.9% sodium chloride solution, was administered intravenously by constant infusion over a 4-hour period starting at 9:00 a.m. Urine was collected in 4-hour samples for the determination of OHPr, P, and creatinine. Blood for determination of Ca, P, creatinine, and OHPr was drawn at appropriate times.3) Prolonged calcium infusions. Calcium glucoheptonate was given by continued iv infusion to three patients with hypoparathyroidism for 4 consecutive days while they were on a balance regimen similar to that used in the first group of experiments. The dosage of calcium averaged 7.5, 12.5, and 22.0 mg per kg per day in the three subjects, respectively. The 8 days before and after the infusion served as control periods. Blood was analyzed daily for Ca and P, and urine was collected daily for the determination of P, OHPr, and creatinine.Chemical assays. Samples of diets, urine, and feces were analyzed for P by the method of Fiske and SubbaRow (17), for total nitrogen by the method of Kjeldahl (18), and for Ca by flame photometry; samples of urine were analyzed for creatinine (19). Total OHPr was determined in hydrolyzed samples of urine and homogenized feces by the method of Prockop and Udenfriend (20). At varying levels of OHPr excretion, less than 3% of the total urinary OHPr was found to be the free amino acid; the remainder is presumed to be peptide-bound. Analysis of samples of fecal homogenate by the method 1073

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Section: Resultsmentioning

confidence: 99%

Relation between Urinary Hydroxyproline and Parathyroid Function*

Keiser¹,

Gill²,

Sjoerdsma³

et al. 1964

J. Clin. Invest.

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“…Odontoclasts seem to play an important role in root resorption. However, studies of odontoclasts (Yaeger and Kraucunas, 1969;Freilich, 1971) are still few in comparison with those on osteoclasts in bone resorption (Hancox and Boothroyd, 1961;Lucht, 1972;Bonucci, 1974;Heersche, 1978;Boyde et al, 1984;Tanaka and Tanaka, 1988). Existing studies have been restricted to the physiological root resorption in deciduous teeth induced by the eruption of permanent teeth (Furseth, 1968).…”

Section: Introductionmentioning

confidence: 97%

Endocytosis in Odontoclasts and Osteoclasts Using Microperoxidase as a Tracer

et al. 1990

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Microperoxidase (MP, a peptide tracer) was intravenously injected into rats after six days of tooth movement by the Waldo method. Bone resorption was seen along the distal bone surface of the inter-radicular septum of the upper first molar, and tooth root resorption occurred along the mesial and distal surfaces of the distal root of the same molar. Odontoclasts were smaller in size and numbers than osteoclasts, but had the same organelles [multiple nuclei, ruffled borders (RB), clear zones, vacuoles, mitochondria, and specific granules] as osteoclasts. MP was deposited on the resorbed area through the clear zone and was transported into the vacuoles along the channels of the RB. The uptake of MP by odontoclasts was small, compared with that by osteoclasts. Collagen fibrils were found in the channels of the RB but were not detected in the vacuoles. Instead, filament-like structures were seen in the vacuoles and were located very near the collagen fibrils in the channels. Fibroblasts outside the resorbed lacunae had endocytosed collagen. In contrast, some cells close to odontoclasts (osteoclasts) in the dentin (bone)-resorbed lacunae had not endocytosed any collagen fibrils. These findings suggest (1) that odontoclasts resorb the dentin or cementum just as osteoclasts do in bone resorption, (2) that the resorbed area connects with the extracellular spaces of the odontoclasts or osteoclasts, and (3) that the organic components (e.g., collagen fibrils) of dentin or cementum are endocytosed through the channels of the RB in the same manner as that for MP. However, the endocytotic ability of odontoclasts appears inferior to that of osteoclasts.

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“…4 The brush or ruffled border of the osteoclast actively sweeps across the bone or dentin to produce the enzymatic destruction of the connective tissue matrix and the dissolution of the minerals contained in this matrix. 5 It has been found that gallium is absorbed preferentially in bone and that, as a consequence, gallium increases the stabilizing of hydroxyapatite crystals. 6,7 Other investigators suggested that gallium can be absorbed into the inorganic crystalline substructure of bone or dentin, which alters the material enough to resist specifically dissolution by the osteoclast.…”

Section: Introductionmentioning

confidence: 99%

Gallium Diffusion in Human Root Dentin: Quantitative Measurements by Pulsed Nd:YAG Laser Ablation Combined with an Inductively Coupled Plasma Mass Spectrometer

Ghazi

Shuttleworth²,

Angulo

et al. 2000

Journal of Clinical Laser Medicine & Surgery

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Even the lowest concentrations of gallium found in peripheral root dentin exceeded the 10(-4) M concentration required to inhibit osteoclastic activity. This simple endodontic treatment should undergo clinical trials to determine its efficacy in vivo. The laser ablation, inductively coupled mass spectrometry method is a powerful analytic tool for measuring spatial distribution of materials in mineralized tissues.

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Motion Picture and Electron Microscope Studies on the Embryonic Avian Osteoclast

Cited by 94 publications

References 15 publications

Relation between Urinary Hydroxyproline and Parathyroid Function*

Relation between Urinary Hydroxyproline and Parathyroid Function*

Endocytosis in Odontoclasts and Osteoclasts Using Microperoxidase as a Tracer

Gallium Diffusion in Human Root Dentin: Quantitative Measurements by Pulsed Nd:YAG Laser Ablation Combined with an Inductively Coupled Plasma Mass Spectrometer

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