Abstract:
:To investigate the possible role of calmodulin in the calcium sensitivity of parathyroid adenylate cyclase (AC), the effect of the calmodulin inhibitor trifluoperazine hydrochloride (TFP) on the calcium sensitivity of forskolin-stimulated AC activity was investigated in membranes prepared from normal porcine parathyroid glands. TFP inhibited AC in a concentration-dependent manner, the IC50 being approximately 100 microM. The inhibition of the enzyme occurred at roughly the same concentration of TFP in the presence and absence of calcium. Another calmodulin inhibitor, N-(6-aminohexyl)-chloro-1-naphthalenesulfonamide (W-7), also inhibited AC in a calcium-independent manner with a IC50 of approximately 200 microM. The pattern of calcium inhibition of AC was compared in membranes prewashed with either EGTA or 2 microM ionic calcium plus 100 microM TFP in an attempt to remove endogenous calmodulin. Neither treatment significantly altered the apparent affinities of the two previously reported calcium inhibition sites, nor did they alter the relative contribution of the individual calcium inhibition sites to the overall calcium inhibition. Inclusion of 100 microM TFP in the incubation mixture resulted in no change in the apparent affinities of the calcium inhibition site although it did result in a significant decrease in the relative contribution of the high affinity site (P less than 0.05). Addition of exogenous calmodulin (5-50 micrograms/ml) had no significant effect on AC. We conclude from these studies that the inhibition of parathyroid AC by calcium is independent of calmodulin and that this enzyme has intrinsic high sensitivity to calcium.
journal_name
Calcif Tissue Intjournal_title
Calcified tissue internationalauthors
Oldham SB,Lipson LGdoi
10.1007/BF02556606subject
Has Abstractpub_date
1986-05-01 00:00:00pages
275-81issue
5eissn
0171-967Xissn
1432-0827journal_volume
38pub_type
杂志文章abstract::Alkaptonuria (AKU) is characterised by increased circulating homogentisic acid and deposition of ochronotic pigment in collagen-rich connective tissues (ochronosis), stiffening the tissue. This process over many years leads to a painful and severe osteoarthropathy, particularly affecting the cartilage of the spine and...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-020-00764-6
更新日期:2021-02-01 00:00:00
abstract::The purpose of this study is to estimate the efficacy of eldecalcitol (1α, 25-Dihydroxy-2β- (3-hydroxypropyloxy) vitamin D3; ELD) on bone metabolism after long-term administration. Six-month-old Wistar-Imamichi rats were ovariectomized (OVX) and administered ELD orally at doses of 7.5, 15, or 30 ng/kg daily. Bone mine...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-014-9937-5
更新日期:2015-01-01 00:00:00
abstract::Teriparatide (TPTD) is known to increase the cortical thickness and porosity. The purpose of the present study was to determine whether switching from TPTD to ibandronate (IBN) would be useful for improving cortical bone parameters as assessed using high-resolution quantitative computed tomography (HR-QCT) analyses in...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-016-0180-0
更新日期:2016-11-01 00:00:00
abstract::Parathyroid Hormone (PTH) stimulates calcium entry into bone cells in vitro, and this effect has been proposed to mediate the actions of PTH on bone. Using cells harvested from infant rat calvaria by collagenase digestion, we evaluated the sensitivity and specificity of this phenomenon. Calcium uptake was temperature ...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF02408543
更新日期:1980-01-01 00:00:00
abstract::Osteoporosis is a common age-related disease with a strong genetic influence. COLIA1 is one of the most extensively studied candidate genes and has consistently been associated with BMD and fracture. We examined the effects of the polymorphisms -1997G>T, -1663indelT, and +1245G>T and their haplotypes on vertebral frac...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-008-9199-1
更新日期:2009-02-01 00:00:00
abstract::Cortical bone can be modeled as a complex hierarchical composite interrelating both structure and material properties on four levels of structural organization: molecular, ultrastructural, microscopic, and macroscopic. In young animals, the microstructural systems are long parallel lamellar units, plexiform bone, whic...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF02406131
更新日期:1984-01-01 00:00:00
abstract::We treated four hypercalcemic cancer patients by nasal hCT, 3 x 2 mg daily, which has been reported to be active in Paget's disease at lower doses. Only one patient became normocalcemic and mean (+/- SEM) calcium levels fell from 11.6 +/- 0.2 mg/dl before therapy to 10.7 +/- 0.6 mg/dl 2-3 days after starting hCT. The ...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF00296210
更新日期:1992-07-01 00:00:00
abstract::This randomized, double-blind study assessed the antifracture efficacy and safety of intermittent intravenous (IV) ibandronate versus oral daily risedronate in Japanese patients with primary osteoporosis. Ambulatory patients aged ≥60 years were randomized to receive 0.5 or 1 mg/month IV ibandronate plus oral daily pla...
journal_title:Calcified tissue international
pub_type: 杂志文章,随机对照试验
doi:10.1007/s00223-013-9734-6
更新日期:2013-08-01 00:00:00
abstract::To define the quantitative aspects of ossification of human fetal spine, we performed a high resolution densitometric study by lateral and postero-anterior scanning of five fetal spines (18-36 weeks of conceptual age) and one spine of a 4-month-old infant. The data were plotted against developmental age for each spine...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF00299001
更新日期:1995-07-01 00:00:00
abstract::It has been suggested that oxidative stress is associated with the pathogenesis of osteoporosis. The objective of this study was to explore the association between a marker of oxidative stress and either bone turnover markers or bone mineral density (BMD) in postmenopausal women. In addition, the effects of oxidative ...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-010-9393-9
更新日期:2010-09-01 00:00:00
abstract::The existence of nutritional deficiency rickets among infants in sunny Riyadh was confirmed radiologically. Most of the rachitic infants were breast-fed, some received unsupplemented infant feeding formulae, and all live in an environment that is devoid of sunlight. Their mean age at the time of onset was 10.5 months....
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF02405328
更新日期:1984-05-01 00:00:00
abstract::We assessed the relationship of bone density and microarchitecture between hand, peripheral, and axial skeletal sites using high-resolution peripheral quantitative computed tomography (HR-pQCT) and dual-energy X-ray absorptiometry (DXA) in patients with rheumatoid arthritis (RA) and which factors influence these param...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-012-9644-z
更新日期:2012-11-01 00:00:00
abstract::We separated osteoclasts from bone and observed the effect of several known and potential mediators of the control of bone resorption on their cytoplasmic motility. We already found that calcitonin (CT), a hormone that inhibits bone resorption, regularly causes complete inhibition of cytoplasmic motility, specific for...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF02405095
更新日期:1983-07-01 00:00:00
abstract::This study sought to develop a noninvasive, reliable, clinically relevant, and easy-to-implement mouse model that can be used for investigation of the pathophysiology of PTOA and for preclinical testing of new therapies of PTOA. Accordingly, we have established a closed intraarticular tibial plateau compression loadin...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-019-00614-0
更新日期:2020-02-01 00:00:00
abstract::The effect of long-chain n-3 polyunsaturated fatty acid (PUFA) on bone measurements was evaluated in gonad-intact middle-aged male rats. Seven rats were killed on day 0 of dietary intervention to determine bone parameters at baseline. Experimental rats (7/group) were fed one of the following lipid treatments (g/kg die...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-007-9010-8
更新日期:2007-04-01 00:00:00
abstract::It has long been thought that collagen fibers within the bone matrix are deposited in an aligned pattern that channels mineral growth. If this model of bone structure is correct, both organic and inorganic phases of bone should have similar elastic anisotropy. Using an acoustic microscope, we measured longitudinal and...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF00299319
更新日期:1994-11-01 00:00:00
abstract::We measured serum concentrations of bone Gla-protein (osteocalcin, BGP) and carboxyterminal propeptide of type I procollagen (PICP) in 14 patients with active acromegaly. Blood was collected at 0800 for measurement of bone Gla-protein (BGP), carboxyterminal propeptide of type I procollagen (PICP), and insulin-like gro...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF00298716
更新日期:1993-03-01 00:00:00
abstract::The aim of this study was to evaluate the association among phalangeal morphometric parameters, amplitude-dependent speed of sound (AD-SOS), ultrasound bone profile index (UBPI), and spinal bone mineral density (BMD) and fracture status. One hundred women (controls, mean age 53 +/- 12 years) and 40 osteoporotic women ...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-001-1092-0
更新日期:2003-04-01 00:00:00
abstract::Human osteoblasts were obtained by migration and proliferation of cells from embryonic membranous bone on glass fragments. Light and electron microscopy analyses revealed a typical osteoblast-like appearance with high protein synthesis activity. The cells showed high alkaline phosphatase activity that was associated w...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF00316880
更新日期:1992-11-01 00:00:00
abstract::Forty 5-week-old rats were randomly divided into 1 control group given a normal diet and water low in fluoride (0.026 mM/1) and experimental group receiving the same basic diet and a fluoride supplement of 2.6 mMol/l in the drinking water. After 30 weeks, half of the fluoride-supplemented and half of the nonsupplement...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF02405089
更新日期:1983-07-01 00:00:00
abstract::Conventional transmission electron microscopy requires an effective dehydration of the tissue specimens under investigation. This dehydration, for which ethanol most often is used, may influence the solubility of the slightly soluble calcium phosphates. To study the behavior of calcium phosphates in ethanol, stable ne...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF02554840
更新日期:1985-03-01 00:00:00
abstract::Humanin (HN), a mitochondrial derived peptide, plays cyto-protective role under various stress. In this study, we aimed to investigate the effects of HNGF6A, an analogue of HN, on osteoblast apoptosis and differentiation and the underlying mechanisms. Cell proliferation of murine osteoblastic cell line MC3TC-E1 was ex...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-020-00660-z
更新日期:2020-05-01 00:00:00
abstract::The present study examined calcium phosphate precipitation in aqueous suspensions of multilamellar liposomes as a possible in vitro model for matrix vesicle mineralization. Liposomes were prepared by dispersing CHCl3-evaporated thin films of 7:2:1 and 7:1:1 molar mixtures of phosphatidylcholine, dicetyl phosphate, and...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF02405354
更新日期:1984-07-01 00:00:00
abstract::Aluminum ions (Al) and chromium (III) ions (Cr), as they exist in aqueous solution at neutral pH, adsorb onto calcium hydroxyapatite crystals (HAP) and severely inhibit their dissolution process, when present in concentrations less than 1 microM. Iron (III) ions (Fe), at concentrations up to 10 microM, have no effect ...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF02555127
更新日期:1987-07-01 00:00:00
abstract::The effect of teriparatide treatment on microdamage accumulation has yet to be examined in animal studies. The purpose of this study was to investigate the effect of once-weekly teriparatide treatment on bone microdamage accumulation and the relationship between microdamage parameters and bone mass, architecture, turn...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-018-0500-7
更新日期:2019-04-01 00:00:00
abstract::Serum immunoreactive osteocalcin (irOC) consists of two fractions that differ from each other by their affinity for hydroxyapatite. The high and low affinity fractions are referred to as irOCbound and irOCfree, respectively. To evaluate whether these fractions are determinants for different characteristics of bone or ...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s002239900543
更新日期:1998-11-01 00:00:00
abstract::Mice deficient in the chloride channel ClC-7, which is likely involved in acidification of the resorption lacuna, display severe osteopetrosis. To fully characterize the osteopetrotic phenotype, the phenotypes of osteoclasts and osteoblasts were evaluated. ClC-7(-/-) mice and their corresponding wild-type littermates ...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-008-9185-7
更新日期:2008-12-01 00:00:00
abstract::The tumor-suppressor p53 is a transcription factor that regulates a number of genes in the process of cell-cycle inhibition, apoptosis, and DNA damage. Recent studies have revealed a crucial role for p53 in bone remodeling. In our previous studies we have shown that p53 is an important regulator of osteoblast differen...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s00223-011-9533-x
更新日期:2011-11-01 00:00:00
abstract::Alkaline phosphatase is detected in both soluble and particulate fractions of rat bone. The concentration of alkaline phosphatase in the particulate fraction of rat skull cap bone and femur is high during the peak period of calcification of these bones suggesting the possibility of using it as a marker for the rate of...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/BF02555116
更新日期:1986-09-01 00:00:00
abstract::Hip fracture may cause and/or complicate institutionalization. We undertook this study to define its overall prevalence among the residents of four nursing homes in Central Italy as well as its latency and impact on mobility when it occurred within institutions. We also performed a case control analysis with the aim o...
journal_title:Calcified tissue international
pub_type: 杂志文章
doi:10.1007/s002230001212
更新日期:2001-06-01 00:00:00