Histochemical Distribution of 5-Nucleotidase in Snake Tissues: Presence of 5-Nucleotidase and Absence of Alkaline Phosphomonoesterase in Venom Glands of the Rattlesnake

1952 ◽  
Vol s3-93 (24) ◽  
pp. 391-394
Author(s):  
D. E. BRAGDON ◽  
J.F. A. MCMANUS
Keyword(s):  
Alkaline Phosphatase ◽  
Smooth Muscle ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Venom Gland ◽  
Specific Alkaline Phosphatase ◽  
Rattlesnake Venom ◽  
Great Vessels ◽  
Venom Glands ◽  
Thyroid Epithelium

1. Activity of the specific alkaline phosphatase, 5-nucleotidase, is intense in the epithelium and secretion of the rattlesnake venom gland. Non-specific alkaline phosphatase activity is lacking. 2. Thyroid epithelium, the smooth muscle of great vessels, and (inconstantly) smooth muscle of abdominal hollow viscera show greater 5-nucleotidase than nonspecific activity. 3. These findings confirm the specificity of 5-nucleotidase.

Abstract 300: Leptin Promotes the Osteoblast Differentiation and Mineralization of Primary Cultures of Vascular Smooth Muscle Cells by Regulating GSK-3β

2012 ◽  
Vol 32 (suppl_1) ◽  
Author(s):  
Melec G Zeadin ◽  
Martin K Butcher ◽  
Geoff H Werstuck
Keyword(s):  
Alkaline Phosphatase ◽  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Phosphatase Activity ◽  
Vascular Calcification ◽  
Alkaline Phosphatase Activity ◽  
Osteoblast Differentiation ◽  
Muscle Cells ◽  
Dependent Manner ◽  
Gsk 3Β

Obesity is an independent risk factor for cardiovascular disease (CVD) although the precise molecular mechanisms that link obesity to CVD are not understood. Recent studies suggest that factors secreted by adipose tissue may play an adverse role in cardiovascular health. We have previously demonstrated that the adipocytokine, leptin, promotes vascular calcification in apolipoprotein E - deficient mice and that this increase in calcification is associated with an increase in the expression of several osteoblast-specific markers within the vessel wall. In an effort to understand the mechanism by which leptin exerts these effects, we cultured primary bovine aortic smooth muscle cells (BASMCs) in the presence of 0 to 2 μg/ml leptin for up to 12 days. Osteogenic differentiation of BASMCs was determined by an increase in the expression of osteoblast-specific markers, and the induction of both alkaline phosphatase activity and mineralization. Consistent with previous studies, we found that treatment of BASMCs with leptin induced osteoblast differentiation in a dose-dependent manner. To investigate the underlying mechanism, we examined changes in the expression levels of key factors implicated in osteoblast differentiation, including members of the Wnt signaling pathway. We found that exposure to leptin induced the Erk 1/2-dependent inactivation of GSK-3β, through Ser9 phosphorylation, and a subsequent increase in the nuclear accumulation of β-catenin. Transfection of BASMCs with an adenovirus that expressed constitutively active GSK-3β (Ad-GSK-3β S9A) resulted in a > 2-fold increase in GSK-3β activity, a decrease in the expression of the osteoblast-specific marker, osteopontin, and a significant decrease in leptin-induced alkaline phosphatase activity. Together, our results provide a possible mechanism by which elevated leptin concentrations, associated with obesity, promote osteoblast differentiation, and vascular calcification in vivo.

Serum Osteocalcin, Total and Bone-Specific Alkaline Phosphatase following Isolated Tibial Shaft Fracture

1996 ◽  
Vol 33 (3) ◽  
pp. 196-200 ◽  
Author(s):  
Shirley A Bowles ◽  
Nazeer Kurdy ◽  
Alison M Davis ◽  
Michael W France ◽  
David R Marsh
Keyword(s):  
Alkaline Phosphatase ◽  
Phosphatase Activity ◽  
Alkaline Phosphatase Activity ◽  
Healing Process ◽  
Shaft Fracture ◽  
Tibial Shaft Fracture ◽  
Tibial Shaft ◽  
Post Injury ◽  
Specific Alkaline Phosphatase ◽  
Bone Specific Alkaline Phosphatase

We report the changes in osteocalcin concentrations and in total and bone specific alkaline phosphatase activity occurring in the twenty week period following tibial shaft fracture in 20 subjects. Bone formation during the healing process is reflected by progressive increases in the concentration of osteocalcin and bone specific alkaline phosphatase after week 5 and the latter correlated with the height and weight of the subject. In the early post injury period, total alkaline phosphatase activity increased whereas that of the bone isoenzyme initially fell, starting to rise again during the second week. After an immediate post injury rise, osteocalcin concentration also decreased, reaching a nadir by week 5. As only three of our subjects demonstrated delayed union, we have not been able to demonstrate that biochemical monitoring of the healing process can provide an indication of prognosis in tibial shaft fracture.

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