scholarly journals Diurnal variability in alkaline phosphatase activity and the potential role of zooplankton

2019 ◽  
Vol 4 (3) ◽  
pp. 71-78 ◽  
Author(s):  
C. Davis ◽  
M. C. Lohan ◽  
R. Tuerena ◽  
E. Cerdan‐Garcia ◽  
E. M. S. Woodward ◽  
...  
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Potential Role ◽  
Diurnal Variability

Acidosis inhibits osteoblastic and stimulates osteoclastic activity in vitro

1992 ◽  
Vol 262 (3) ◽  
pp. F442-F448 ◽  
Author(s):  
N. S. Krieger ◽  
N. E. Sessler ◽  
D. A. Bushinsky
Keyword(s):  
Alkaline Phosphatase ◽  
Metabolic Acidosis ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Collagen Synthesis ◽  
Calcium Flux ◽  
Osteoclastic Activity ◽  
Glucuronidase Activity

Metabolic acidosis induces net calcium flux (JCa) from cultured neonatal mouse calvariae through physicochemical and cell-mediated mechanisms. To determine the role of osteoblasts in acid-induced JCa, collagen synthesis and alkaline phosphatase activity were assessed in calvariae incubated in reduced pH and bicarbonate medium, a model of metabolic acidosis (Met), and compared with controls (Ctl). Collagen synthesis fell from 30.5 +/- 1.1 in Ctl to 25.1 +/- 0.4% with Met, and alkaline phosphatase decreased from 403 +/- 25 in Ctl to 298 +/- 21 nmol Pi.min-1.mg protein-1 with Met. During acidosis JCa was correlated inversely with percent collagen synthesis (r = -0.743, n = 11, P = 0.009) and with alkaline phosphatase activity (r = -0.453, n = 22, P = 0.034). To determine the role of osteoclasts in acid-induced JCa, osteoclastic beta-glucuronidase activity was determined in Ctl and Met in the absence or presence of the osteoclastic inhibitor calcitonin (CT, 3 x 10(-9) M). Met increased beta-glucuronidase (5.9 +/- 0.2) compared with Ctl (4.6 +/- 0.3 micrograms phenolphthalein released.bone-1.h-1), whereas CT inhibited beta-glucuronidase in both Ctl and Met (3.1 +/- 0.2 and 3.5 +/- 0.3, respectively). During acidosis JCa was correlated directly with beta-glucuronidase activity (r = 0.683, n = 42, P less than 0.001). Thus the cell-mediated component of JCa during acidosis in vitro appears to result from a combination of inhibited osteoblastic and stimulated osteoclastic activity.

RICKETS, DEFICIENCY OF "ALKALINE" PHOSPHATASE ACTIVITY AND PREMATURE LOSS OF TEETH IN CHILDHOOD

PEDIATRICS ◽  
1953 ◽  
Vol 11 (4) ◽  
pp. 309-322
Author(s):  
EDNA H. SOBEL ◽  
LELAND C. CLARK ◽  
R. PHYLLIS FOX ◽  
MEINHARD ROBINOW
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Enzyme Treatment ◽  
Deciduous Teeth ◽  
Local Factor ◽  
Plasma Alkaline Phosphatase ◽  
Serum Inorganic Phosphate ◽  
Genetically Determined

A child, studied between the ages of 1½ and 3½ years, presented an abnormally low plasma alkaline phosphatase activity (0.8-1.64 Bessey-Lowry u.), a deformed skeleton and the loss of most of her deciduous teeth. The serum Ca was normal; the serum inorganic phosphate remained at the normal relatively high levels of infancy as the child grew older Roentgenograms demonstrated deficient mineralization of the skeleton and teeth. Biopsies of the liver and the costochondral junction displayed a deficiency of tissue alkaline phosphatase activity. The architecture of the rib was consistent with rickets. There was no evidence for the presence of an inhibitor of alkaline phosphatase, such as beryllium, or for an excessive excretion of the enzyme. Treatment with purified growth hormone, ascorbic acid and thiamin chloride had no effect, while vitamin D 500 thousand u. caused little change in the enzyme activity in a 10 day period. The father had low plasma alkaline phosphatase activity and a number of similar patients are mentioned, for whom there was also evidence that the deficiency in alkaline phosphatase activity may be genetically determined. While the precise role of alkaline phosphatase activity in the metabolism of bone is not clear, the findings in this patient suggest that growing bone may require the presence of alkaline phosphatase for normal calcification, and that the skeletal disorder, which could not be distinguished from rickets, may be related to a disturbance in the local factor.

Alkaline phosphatase activity in the plasma of children and adolescents.

1977 ◽  
Vol 23 (3) ◽  
pp. 469-472 ◽  
Author(s):  
G A Fleisher ◽  
E S Eickelberg ◽  
L R Elveback
Keyword(s):  
Alkaline Phosphatase ◽  
Public Schools ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Serum Alkaline Phosphatase ◽  
Intraclass Correlation ◽  
Serum Alkaline Phosphatase Activity ◽  
Upper Limits ◽  
Prepubertal Girls

Abstract We determined plasma (serum alkaline phosphatase activity in 854 healthy students of the Rochester, Minnesota, public schools. Prepubertal girls had somewhat greater upper limits than did boys, and there was a low trend of increasing activity in both sexes. At the beginning of adolescence increasing activities were observed, which peaked at ages 11 to 12 years in girls and at ages 13 to 14 in boys. Adult values were not reached until six to eight years later. In 180 pairs of siblings, a significant intraclass correlation was noted. A possible role of alkaline phosphatase in the regulation of protein synthesis is suggested.

Circulating levels of 1,25 dihydroxyvitamin D, alkaline phosphatase, hydroxyproline, and osteocalcin associated with antler growth in white-tailed deer

1988 ◽  
Vol 118 (3) ◽  
pp. 407-414 ◽  
Author(s):  
Karen L. Van Der Eems ◽  
Robert D. Brown ◽  
Caren M. Gundberg
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Serum Alkaline Phosphatase ◽  
Serum Samples ◽  
Serum Alkaline Phosphatase Activity ◽  
Dihydroxyvitamin D ◽  
Antler Growth ◽  
Antler Cycle

Abstract. Alkaline phosphatase, hydroxyproline, osteocalcin, and 1,25(OH)2D were measured in biweekly serum samples obtained from 6 adult (> 4 years), 4 juvenile (1–4 years) and 4 fawn (< 1 year) male white-tailed deer from Oct. 1983 to Oct. 1984. Antler length, from the pedicle to the tip, was measured at the time of serum sampling. Serum alkaline phosphatase activity and levels of hydroxyproline and osteocalcin were higher (P < 0.05) in fawns compared with juveniles and adults reflecting increased bone metabolism in the younger deer. In adult deer serum alkaline phosphatase activity and hydroxyproline levels were elevated (P < 0.05) during the period of antler growth, whereas serum osteocalcin and 1,25(OH)2D increased (P < 0.05) during antler mineralization. Similar but less pronounced trends occurred in juvenile deer, possibly a reflection of skeletal growth in the younger animals. The data lend support for utilization of the deer antler cycle as a model for studies of bone disorders. Further work is needed to help clarify the role of hydroxyproline, osteocalcin, and 1,25(OH)2D in the antler cycle.

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