Enzymatic and electron microscopic analysis of isolated osteoclasts

Walker, Donald G.

doi:10.1007/bf02061969

Cited by 50 publications

(13 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…CT appears to exert its effects primarily on cells that have osteoclastic characteristics determined by high levels of acid phosphatase activity [16] and the ability to resorb bone [17]. Unlike the studies of Wong and Cohn, which reported hormonal effects only after the resident populations were cultured to confluency, our data provide evidence that these hormonally sensitive cells are present in 19-21-day rat fetus and 1-2-day newborns.…”

Section: Discussioncontrasting

confidence: 61%

Calcitonin effects on isolated bone cells

et al. 1982

View full text Add to dashboard Cite

Calcitonin decreased calcium uptake in specific rat bone cell populations obtained by sequential collagenase digestions of calvaria. The calcitonin effect on calcium uptake was observed in the same populations that manifested calcitonin-induced increases in cyclic AMP as well as high levels of acid phosphatase and the ability to release 45Ca from prelabeled devitalized bone. No effect of calcitonin was observed in cell populations that had high levels of alkaline phosphatase and lacked the potential to resorb devitalized bone. These results suggest that changes in cell calcium as well as cyclic AMP may be involved in the mode of action of calcitonin on osteoclast-like cells.

show abstract

Section: Discussioncontrasting

confidence: 61%

Calcitonin effects on isolated bone cells

et al. 1982

View full text Add to dashboard Cite

show abstract

“…Several hydrolytic enzymes are'believed to be involved in bone remodeling. Bone acid phosphatase has been found to be most abundant in osteoclasts [17], and the enzyme has long been known to be localized at sites of active bone resorption [18,19]. Bone alkaline phosphatase, on the other hand, has been demonstrated to have its highest activity in areas of bone undergoing mineralization [20][21][22].…”

Section: Introductionmentioning

confidence: 99%

Metabolic aspects of bone resorption in calcium-deficient lactating rats

1980

View full text Add to dashboard Cite

Lactating female rats were fed diets containing 1.0, 0.1, or 0.04% Ca for 21 days. Fat-free dry weight, ash weight, calcium and phosphorus content of the humerus, plasma calcium levels, and bone acid and alkaline phosphatase activities were compared to those of nonlactating rats fed the same diets. Bone, plasma, and urinary cAMP levels were also studied. Dietary calcium deficiency and/or lactation caused significant loss of bone mass from experimental animals. Urinary cAMP levels reflecting increased parathyroid activity were elevated by the stresses of lactation and calcium deficiency over those of control animals. Plasma and bone levels of cAMP were not different. Bone alkaline and acid phosphatase activities were affected only by the most extreme stress. The results demonstrated that the calcium-deficient lactating rat is an excellent model for bone resorption studies.

show abstract

“…SHOLLEY multinucleate osteoclasts (Walker, 1972;1961), suggests, as does their absence of ruffled borders and relatively slight acid phosphatase activity, that such multinucleate variants lack bone resorption activity. Unlike the multinucleate osteoblast-like cells recently described by Ejiri (19831, the ones in the present study possessed few osteoclastic characteristics.…”

Section: Discussionmentioning

confidence: 95%

A comparative study of osteoblasts: In situ versus isolated specimens

1985

View full text Add to dashboard Cite

Osteoblasts and osteoclasts are known to adhere tenaciously to bone surfaces even when the fibrous periosteal covering is removed. Brush-smear isolates and in situ, whole bone mounts of the osteogenic periosteum on the inner and outer calvarial tables of young adult rats were examined at the light microscopic level after exposing the cells by removing the fibrous periosteum. Based on staining, enzymatic activity, and overall morphology, most of the cells could be classified as osteogenic in nature. However, detailed analysis revealed that some cells exhibited certain unique morphologic appearances that suggested the existence of subpopulations or variant forms of the conventional or prototypic osteoblast. Three variant forms were the large nucleate, small nucleate, and multinucleate osteoblast-like cells, the latter with nuclear numbers ranging from 2-10. The finding of all such forms in smears, short-term cell cultures, and in situ specimens greatly lessened the probability that the unusual forms were artifactual. Phase contrast microscopic studies and sectioning of cellular isolates for study at both the light and electron microscopic levels provided additional support for the existence of the multinucleate osteoblast-like cell. The small size of these osteoblast-like subpopulations and the orientation of the cells to the commonly used plane of section of most histologic bone specimens, particularly with the multinucleate type, could explain why they had escaped earlier detection.

show abstract

Enzymatic and electron microscopic analysis of isolated osteoclasts

Cited by 50 publications

References 12 publications

Calcitonin effects on isolated bone cells

Calcitonin effects on isolated bone cells

Metabolic aspects of bone resorption in calcium-deficient lactating rats

A comparative study of osteoblasts: In situ versus isolated specimens

Contact Info

Product

Resources

About