Looking for 1,25-dihydroxycholecalciferol? Find out information about 1,25-dihydroxycholecalciferol. 1,25-dihydroxycholecalciferol, the form of vitamin D that is involved in intestinal absorption of Ca2+and Ca2+resorption by bone Explanation of 1,25-dihydroxycholecalciferol
Antibodies to 1 alpha, 25-dihydroxy vitamin D3 25-hemisuccinate linked to albumin were produced and an immunoassay for 1,25-dihydroxy vitamin D developed. Plasma 1,25-dihydroxy vitamin D concentrations were compared using an immunoassay and cytosol radioreceptor assay. Both assays gave comparable results but the immunoassay was more reproducible, slightly more sensitive and had a lower detection limit. Using the immunoassay the plasma 1,25-dihydroxy vitamin D was 110.5 pmol/l (S.D. 29.4) in normal subjects; there was no difference between males and premenopausal females. It was negatively related to plasma phosphate. In renal failure and primary hyperparathyroidism plasma 1,25(OH)2D was positively related to radiocalcium absorption. Following 1 and 2 microgram of 1,25-dihydroxy vitamin D3 given orally the peak plasma concentration occurs within 12 h.
TY - JOUR. T1 - Plasma 1,25(OH)2 vitamin d measured by radioimmunoassay and cytosol radioreceptor assay in normal subjects and patients with primary hyperparathyroidism and renal failure. AU - Peacock, Munro. AU - Taylor, G. A.. AU - Brown, Wendy. PY - 1980/2/14. Y1 - 1980/2/14. N2 - Antibodies to 1α,25-dihydroxy vitamin D3 25-hemisuccinate linked to albumin were produced and an immunoassay for 1,25-dihydroxy vitamin D developed. Plasma 1,25-dihydroxy vitamin D concentrations were compared using an immunoassay and cytosol radioreceptor assay. Both assays gave comparable results but the immunoassay was more reproducible, slightly more sensitive and had a lower detection limit. Using the immunoassay the plasma 1,25-dihydroxy vitamin D was 110.5 pmol/l (S.D. 29.4) in normal subjects; there was no difference between males and premenopausal females. It was negatively related to plasma phosphate. In renal failure and primary hyperparathyroidism plasma 1,25(OH)2D was positively related to radiocalcium ...
Parenteral 1,25-dihydroxycholecalciferol in hepatic osteomalacia.: Despite regular long-term parenteral vitamin D2 treatment, four patients with biliary cirrhos
Disclosed is a pharmaceutical composition in dosage unit form which comprises a dosage effective for the treatment of pains and pyrexia, hypertension, hypotension, hyperlipemia, inflammatory diseases or diseases due to the functional accentuation of thrombocytes of a compound of 24,25-dihydroxycholecalciferol and a pharmaceutical acceptable carrier or diluent therefor.
To investigate the effects of ultraviolet A (UVA) and ultraviolet B (UVB) on serum 1,25-dihydroxy-vitamin D3 and bone metabolism of ovariectomized rats and to compare them on bone metabolism. In the study, 40 six-month female Sprague-Dawley rats were randomly divided into sham-operated control group (sham), osteoporosis model group (OVX), UVA ...
Between Sept 3, 2014 and May 2, 2016, 14 patients were enrolled: CP class A:B, 6:8; median age, 62 (range: 43 to 74) years; male:female, 10:4. Twelve of the 14 patients completed six cycles of treatment; one was withdrawn from the study due to possible study drug-related liver injury (grade 3) in the 160mg/m2/day dose cohort and one withdrew for personal reasons. Serious adverse events occurred in three patients [21% (3/14)], one of which was possibly related to PRI-724. The most common adverse events were nausea [29% (4/14)] and fatigue [21% (3/14)]. After PRI-724 administration, the CP scores worsened by 1 point in two patients in the 10mg/m2/day cohort, improved in three patients at 1, 1, and 2 points in the 40mg/m2/day cohort, and improved in one patient by 3 points in the 160mg/m2/day cohort. The histology activity index scores of the liver tissue improved in two patients and exacerbated in two patients in the 10mg/m2/day cohort, and improved in one patient in the 40mg/m2/day cohort.. ...
Supplementary MaterialsSupplementary Statistics. while treatment with particular inhibitors indicated that hypoxia upregulates HBEGF biosynthesis through anybody from the three analyzed MAPKs.2, 3 However, it had been unclear whether this MAPK pathway was functional or downstream of HBEGF shedding upstream. As a result, MMP2 was quantified in individual TB cells cultured at 2% O2 with particular inhibitors of ERK, jNK and p38. These inhibitors didnt impact the upregulation of MMP2 at low O2, recommending which the MAPKs function solely downstream of HBEGF signaling through the ERBB1/4 tyrosine kinases in individual TB cells, as indicated in Amount 9. Although both MMP2 and HBEGF post-transcriptionally are governed by O2, HBEGF upregulation by low O2 or CoCl2 was obstructed by reported that serum degrees of HSP70 are continuous throughout normal being pregnant, but upsurge in women with preeclampsia or preterm PRI-724 irreversible inhibition delivery significantly.49 Elevated circulating HSP70 ...
The firm announced the close of an approximately $15 million Series C financing. Proceeds will be used to fund clinical trials of Prisms lead compound, PRI-724, for the treatment of fibrosis and other related conditions
Tacalcitol (1,24-dihydroxyvitamin D3) is a synthetic vitamin D3 analog. Tacalcitol is marketed under several names, including Curatoderm and Bonalfa. Tacalcitol reduces excessive cell turnover in the epidermis by interacting with vitamin D receptors on keratinocytes. It is usually prescribed by a general practitioner or dermatologist for the treatment of psoriasis, chronic chapped lips and other severe dry skin conditions because of its ability to reduce excessive skin cell turnover. It is available as an ointment or lotion. It has also been used for vitiligo and Hailey-Hailey disease. Fukuoka M, Sakurai K, Ohta T, Kiyoki M, Katayama I (2001). "Tacalcitol, an active vitamin D3, induces nerve growth factor production in human epidermal keratinocytes". Skin Pharmacol. Appl. Skin Physiol. 14 (4): 226-33. doi:10.1159/000056351. PMID 11464105. Leone G, Pacifico A, Iacovelli P, Paro Vidolin A, Picardo M (March 2006). "Tacalcitol and narrow-band phototherapy in patients with vitiligo". Clin. Exp. ...
F. Cundy, J. A. Kanis, G. Heynen, M. Earnshaw, T. L. Clemens, J. L. H. ORiordan, A. L. Merritt, J. E. Compston; Lack of Direct Effect of 1,25-Dihydroxy-Vitamin D3 on Mineralization of Bone and Secretion of Parathyroid Hormone. Clin Sci (Lond) 1 September 1980; 59 (3): 15P. doi: https://doi.org/10.1042/cs059015P. Download citation file:. ...
1. 1,25-Dihydroxycholecalciferol (1,25-(OH)2-D3) was given at a dose of 5-0 nmol (2-1 mug) daily by mouth for 4-12 days to three patients with hypophosphataemic (type I), vitamin D-resistant rickets. 2. 1,25-(OH)2-D3 increased intestinal absorption and urinary excretion of calcium without
Tacalcitol | VDR agonist | PRI 2191 | 1α,24-Dihydroxycholecalciferol | PRI2191 | CAS [57333-96-7] | Axon 2516 | Axon Ligand™ with >98% purity available from supplier Axon Medchem, prime source of life science reagents for your research
We have examined the effects of the seco-steroid hormone 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] on membrane phosphoinositide metabolism, protein kinase C (PKC) activation and influx of extracellular Ca2+ in chick-embryo muscle-cell (myoblast) cultures. At physiological concentrations, the hormone induces a rapid (15 s) and transient release of inositol triphosphate (InsP3) and diacylglycerol (DAG). InsP3 release is maximal at 60 s (80% above controls) and then declines. The effects of 1,25(OH)2D3 on InsP3 production exhibited specificity, as 25-hydroxy-vitamin D3 and 24,25-dihydroxy-vitamin D3 did not alter myoblast InsP3 levels. The stimulation of DAG is biphasic, with peaks at 60 s (+105%) and 5 min (+700%). The second phase of DAG release is not associated with changes in InsP3. 1,25(OH)2D3 induces a rapid (within 60 s) accumulation of InsP2, and its effect on InsP is delayed (120 s). The hormone rapidly activates myoblast PKC, with maximal translocation of activity from the cytosol to the ...
The optimal range of 1,25-dihydroxy vitamin D in adult men and women ranges from 18 to 64 and 18 to 78 picograms per milliliter, respectively, according to Mayo Clinic. The normal range for males and...
The active vitamin D metabolite 1 25 D3 (1 25 has been proven to be a significant regulator of innate and adaptive immune function. gene appearance which treatment using a physiological focus of 25(OH)D3 down-regulated IFN-γ and IL-17F gene appearance ...
Calcitriol (1,25-dihydroxycholecalciferol), the active form of vitamin D is known to have anti-tumor activity both in vitro and in vivo in a wide variety of malignant cell types. Calcitriol is not only anti-proliferative ...
Boc Sciences offers cas 40013-87-4 24, 25-Dihydroxy VD3 in bulk,please inquire us to get a quote for 40013-87-4 24, 25-Dihydroxy VD3.
Vitamin D is a generic designation for a group of fat-soluble, structurally similar sterols including ergocalciferol D2 from plants and cholecalciferol D3 from animals. Vitamin D in the body is derived from 2 sources: exogenous (dietary: D2 and D3) and endogenous (biosynthesis: D3). Endogenous D3 is produced in the skin from 7-dehydrocholesterol, under the influence of ultraviolet light. Both forms of vitamin D are of similar biologic activity.. Vitamin D is rapidly metabolized in the liver to form 25-hydroxy (OH) vitamin D. Additional hydroxylation of 25-OH vitamin D takes place in the kidney by 1-alpha hydroxylase, under the control of parathyroid hormone, to yield 1,25-dihydroxy vitamin D.. 1,25-Dihydroxy vitamin D is the most potent vitamin D metabolite. It stimulates calcium absorption in the intestine and its production is tightly regulated through concentrations of serum calcium, phosphorus, and parathyroid hormone.. 1,25-Dihydroxy vitamin D levels may be high in primary ...
1. The rapid stimulation of intestinal Ca2+transport observed in vitamin D-deficient chicks after receiving 1,25-dihydroxycholecalciferol has necessitated a re-evaluation of the correlation hitherto observed between this stimulation and the induction of calcium-binding protein synthesis. By 1h after a dose of 125ng of 1,25-dihydroxycholecalciferol, Ca2+transport is increased. This is at least 2h before calcium-binding protein can be detected immunologically and 1h before synthesis of the protein begins on polyribosomes, and thus the hormone stimulates Ca2+transport before calcium-binding-protein biosynthesis is induced. 2. The maximum increase in Ca2+transport observed after this dose of 1,25-dihydroxycholecalciferol (attained by 8h) is similar to that observed after 1.25-25μg of cholecalciferol, but the stimulation is only short-lived, in contrast with the effect observed after the vitamin. At later times after the hormone, however, when Ca2+transport has declined to its basal rate, the ...
In keeping with Dr. Michael Holick creator of "The UV Advantage", and one among the worlds most highly regarded experts on vitamin D and also the therapeutic advantages of purely natural daylight, if 1 has liver or kidney illness you can become vitamin D deficient. You can have to choose both activated vitamin D or certainly one of its analogs to maintain healthy bones.. Being a graduate student with the College of Wisconsin, Holick and his roommate worked on isolating and figuring out the lively method of vitamin D for their PhD job. About a two yr time frame, they managed to synthesize it. This synthesized type of vitamin D was offered to clients although Dr. Holick was in health care university. Sufferers that experienced bone ailments affiliated with kidney failure, that were wheelchair bound and with extreme bone agony, commenced walking once more.. This active type of vitamin D that is definitely created through the kidneys, is referred to as 125-dihydroxy vitamin D. It can not be found ...
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Vitamin D--metabolism;Calcium;Calcium-Binding Proteins;Potassium;Magnesium;Sodium;Phosphorus;Dihydroxycholecalciferols;Osteocalcin;Cyclic AMP--urine;Obesity;Parathyroid Hormone; ...
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Six hypoparathyroid patients were treated with oral furosemide for 4 days. All six had a significant decrease in serum ionized calcium level from the control period (4.05 ± 0.31 mg/dl) to the furosemide period (3.46 ± 0.26 mg/dl, P , 0.005). In five patients, the decrease in serum ionized calcium concentration occurred in association with an increase in urinary calcium excretion. Although serum immunoreactive parathyroid hormone level increased in five patients, it was insufficient to return serum ionized calcium to control levels. Changes in serum phosphorus, magnesium, or pH could not account for the observed decrease in serum ionized calcium concentration. It is necessary to monitor serum ionized calcium level in hypoparathyroid patients during furosemide therapy. ...
Depression has been linked to (lack of) sunlight exposure and raised intracellular calcium levels. In this pathway, the role of the vitamin D pathway in calcium signaling in depression is shown. Active 1,25-dihydroxy-vitamin D3 is formed from 7-dehydrocholesterol by multiple conversion steps. It associates with RXR and VDR in the nucleus, which stimulates transcription of VDR target genes, resulting in lower intracellular calcium levels. Less sunlight exposure results in lower 1,25-dihydroxyvitamin D3 levels and therefore higher calcium levels ...
TY - JOUR. T1 - The metabolism of 1,25-dihydroxyvitamin D3.. AU - Kumar, Rajiv. PY - 1980/6. Y1 - 1980/6. UR - http://www.scopus.com/inward/record.url?scp=0019030105&partnerID=8YFLogxK. UR - http://www.scopus.com/inward/citedby.url?scp=0019030105&partnerID=8YFLogxK. M3 - Article. C2 - 6894425. AN - SCOPUS:0019030105. VL - 1. SP - 258. EP - 267. JO - Endocrine Reviews. JF - Endocrine Reviews. SN - 0163-769X. IS - 3. ER - ...
Sigma-Aldrich offers abstracts and full-text articles by [Steve Y Rhieu, Andrew J Annalora, Guochun Wang, Caroline C Flarakos, Rose M Gathungu, Paul Vouros, Rita Sigüeiro, Antonio Mouriño, Inge Schuster, G Tayhas R Palmore, G Satyanarayana Reddy].
1α,25-Dihydroxyvitamin D3 (1α,25(OH)2D3) had earlier been regarded as the only active hormone. The newly identified actions of 25-hydroxyvitamin D3 (25(OH)D3) and 24R,25-dihydroxyvitamin D3 (24R,25(OH)2D3) broadened the ...
Optimizing vitamin D protects against cardiovascular disease, autoimmune disease, common infections, and DNA repair and metabolic processes.
To elucidate the biosynthesis of 25-hydroxyvitamin D3-26,23-lactone, two known metabolites of 25-hydroxyvitamin D3--23,25-dihydroxyvitamin D3 and 25,26-dihydroxyvitamin D3--were incubated individually with kidney homogenate prepared from vitamin D-supplemented chickens, a preparation known to produce the lactone from 25-hydroxyvitamin D3. The 25-hydroxyvitamin D3-26,23-lactone produced in vitro was then separated, purified, identified, and quantitated by consecutive straight-phase and reverse-phase high-performance liquid chromatography. 23,25-Dihydroxyvitamin D3 is a far better substrate for production of 25-hydroxyvitamin D3-26,23-lactone than is 25,26-dihydroxyvitamin D3. Production of lactone is highly selective for the natural 23(S)-hydroxy-23,25-dihydroxyvitamin D3 while both epimers of 25,26-dihydroxyvitamin D3 resulted in small amounts of product comigrating with natural lactone. It appears that 23(S),25-dihydroxyvitamin D3, but not 25,26-dihydroxyvitamin D3, is a natural precursor in ...
1. Chromatography measurements indicated that adult rats converted 25-hydroxycholecalciferol into 1,25-dihydroxycholecalciferol at a lower rate than that reported earlier for young animals. In serum, less-polar metabolites were found which probably represented vitamin D esters and vitamin D3.. 2. A low dietary intake of calcium resulted in an evident increase in the fraction corresponding to 1,25-dihydroxycholecalciferol in the kidneys and also in the intestinal mucosa and serum.. 3. Inclusion of 0·67 mmol of cadmium/l of drinking water at a low dietary intake of calcium resulted in an increased accumulation of both cadmium and zinc in the kidneys and liver compared with values at a normal dietary calcium intake.. 4. At a normal dietary calcium intake, cadmium exposure caused inhibited production of 1,25-dihydroxycholecalciferol by the kidneys and an increased accumulation of 24,25-dihydroxycholecalciferol, vitamin D3 and vitamin D esters in the serum.. 5. The inhibitory effect of cadmium on ...
1. Chromatography measurements indicated that adult rats converted 25-hydroxycholecalciferol into 1,25-dihydroxycholecalciferol at a lower rate than that reported earlier for young animals. In serum, less-polar metabolites were found which probably represented vitamin D esters and vitamin D3.. 2. A low dietary intake of calcium resulted in an evident increase in the fraction corresponding to 1,25-dihydroxycholecalciferol in the kidneys and also in the intestinal mucosa and serum.. 3. Inclusion of 0·67 mmol of cadmium/l of drinking water at a low dietary intake of calcium resulted in an increased accumulation of both cadmium and zinc in the kidneys and liver compared with values at a normal dietary calcium intake.. 4. At a normal dietary calcium intake, cadmium exposure caused inhibited production of 1,25-dihydroxycholecalciferol by the kidneys and an increased accumulation of 24,25-dihydroxycholecalciferol, vitamin D3 and vitamin D esters in the serum.. 5. The inhibitory effect of cadmium on ...
TY - JOUR. T1 - The dichotomy in the effects of 1,25 dihydroxyvitamin D3 and 24,25-dihydroxyvitamin D3 on bone γ-carboxyglutamic acid-containing protein in serum and bone in vitamin D-deficient rats. AU - Wientroub, Shlomo. AU - Price, Paul A.. AU - Reddi, A Hari. PY - 1987/5. Y1 - 1987/5. N2 - Vitamin D-deficient, second generation, rachitic rats showed significant decrease in bone Gla protein (BGP) levels in circulation and in the skeleton. 1,25 dehydroxyvitamin D3 (1,25 (OH)2D3) exhibited the most potent influence on serum BGP levels in a dose-dependent manner. At a dose 25 ng/100 g body weight 1,25 (OH)2D3 showed a cumulative effect, i.e., the longer the treatment, the more circulating BGP was detected 24,25 dehydroxyvitamin D3 (24,25(OH)2D3) at the same doses did not show similar effect on the serum BGP levels, regardless of the serum calcium levels. Bone BGP levels assayed at various sites representing endochondral and intramenbranous ossification demonstrated an opposite pattern. ...
Article Modifying broiler diets with phytase and vitamin d metabolite (25-OH D3): impact on phosphorus in litter, amended soils, and runoff. Received for publication April 14, 2009. Adding phytase and 25- hydroxycholecalciferol (25-OH D3) to broiler ...
Parathyroid hormone administration to thyroparathyroidectomized rats resulted in a significant reduction in inorganic phosphate content of a variety of striated muscles. Most other organs were...
A method of modifying or altering the structure of a 1α-hydroxylated vitamin D compound to increase its biological activity by altering the conformational equilibrium of the A-ring to favor a chair conformation that presents the 1α-hydroxyl in the axial orientation. This is accomplished by either locking the A-ring chair conformation in a geometry having an axially orientated 1α-hydroxyl, or by the addition of one or more substituents to the A-ring which interact with other substituents in the molecule or on the A-ring to provide a driving force to the A-ring to adopt a chair conformation which presents the 1α-hydroxyl in the axial orientation.
Vitamin D deficiency (hypovitaminosis D) is typically diagnosed by measuring the blood concentration of the 25-hydroxyvitamin D (Calcifediol, Calcidiol), which is a precursor to the active form of the 1,25-dihydroxy-vitamin D (Calcitriol) compound.. The blood concentration of 25-hydroxy-vitamin D reflects vitamin D produced in the skin as well as vitamin D acquired from the foods and has a relatively long circulating half-life of 15 days. It does not, however, reveal the amount of vitamin D stored in other body tissues and organs (muscles, liver, bones etc).. ...
To better understand the extrarenal production of active vitamin D metabolites by cells of the monocyte/macrophage lineage, we investigated the 25-hydroxyvitamin D (25OHD)-1-hydroxylation reaction in the v-myc-transformed chick myelomonocytic cell line HD-11; the 1-hydroxylation reaction in this cell line has a high affinity for 25-hydroxylated vitamin D substrates, is localized to mitochondria, and is associated with cytochrome P450 activity. In this study we demonstrated that the HD-11 cell 1-hydroxylation reaction in vitro is not affected by the majority of extracellular regulatory factors that modulate expression of the renal 25OHD-1-hydroxylase in vivo. A 50% increase in extracellular calcium and phosphate concentrations, physiological inhibitory events for renal 1,25-dihydroxyvitamin D [1,25-(OH)2D] synthesis, did not decrease basal expression of the HD-11 cell 1-hydroxylation reaction, nor did a 50% decrease in extracellular calcium and phosphate concentrations, stimulatory signals for ...
5 µCi quantities of 1 a, 25-[26, 27-3H]-Dihydroxyvitamin D3, are available for your research. Application of [3H] Dihydroxyvitamin D3 can be found in: appearance of the rat testicular receptor during development in steroid biochemistry, in determination as a major intermediate in 25-hydroxyvitamin D3-26,23-lactone formation, receptors in the choroid plexus and ependyma in cellular neuroscience, etc.. ...
TY - JOUR. T1 - C-terminal proteolysis of the avian 1,25-dihydroxyvitamin D3 receptor. AU - Allegretto, Elizabeth A.. AU - Pike, J. Wesley. AU - Haussler, Mark R.. PY - 1987/8/31. Y1 - 1987/8/31. N2 - Exposure of the 60 kDa chick intestinal 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) receptor to carboxypeptidase A resulted in a time dependent decrease in receptor hormone-binding; after 2 h, there was no detectable macro-molecular-bound 1,25(OH)2[3H]D3. Upon DNA-cellulose chromatography of this preparation, a 56 kDa protein adsorbed to the column and eluted as a function of para-chloromercuribenzene sulfonate (a sulfhydryl blocking reagent). The 56 kDa fragment was detected by anti-receptor monoclonal antibodies via immunoblot technology. The 1,25(OH)2[3H]D3 eluted in the fall through fractions of the column. Thus, cleavage of up to 40 amino acids from the carboxy-terminus of the 1,25(OH)2D3 receptor results in a protein which no longer binds to hormone, but retains its capacity to interact with ...
The effect of 1-alpha-hydroxycholecalciferol and parathyroidectomy on cardiovascular lesions in uraemia: an experimental study in the rat ...
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Defective binding and function of 1,25-dihydroxyvitamin D3 receptors in peripheral mononuclear cells of patients with end-organ resistance to 1,25-dihydroxyvita
1. The localisation of intestinal calcium absorption in the rat was studied by means of radioactive45Calcium. Rats were killed 20, 40, and 60 min after oral administration of45CaCl2-solution.45Ca-acti...
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TY - JOUR. T1 - The in vitro evaluation of 25-hydroxyvitamin D3 and 19-nor-1α,25- dihydroxyvitamin D2 as therapeutic agents for prostate cancer. AU - Chen, Tai C.. AU - Schwartz, Gary G.. AU - Burnstein, Kerry L.. AU - Lokeshwar, Bal L.. AU - Holick, Michael F.. PY - 2000/3/1. Y1 - 2000/3/1. N2 - Prostate cancer cells contain specific receptors [vitamin D receptors (VDRs)] for 1α,25-dihydroxyvitamin D3 (1α,25(OH)2D3), which is known to inhibit the proliferation and invasiveness of these cells. These findings support the use of 1α,25(OH)2D3 for prostate cancer therapy. However, because 1α,25(OH)2D3 can cause hypercalcemia, analogues of 1α,25(OH)2D3 that are less calcemic but that exhibit potent antiproliferative activity would be attractive as therapeutic agents. We investigated the effects of two different types of less calcemic vitamin D compounds, 25-hydroxyvitamin D3 [25(OH)D3] and 19-nor-1α,25-dihydroxyvitamin D2 [19-nor-1,25(OH)2D2], and compared their activity to 1α,25(OH)2D3 on ...
25-Hydroxyvitamin D2 and D3 (25-OH-VitD) are steroid hormones that require 1-alpha-hydroxylation before expressing biological activity. Vitamin D compounds are derived from dietary ergocalciferol (from plants, VitD2) or cholecalciferol (from animals, VitD3), or by conversion of 7-dihydrocholesterol to VitD3 in the skin upon ultraviolet exposure. VitD2 and VitD3 are subsequently 25-hydroxylated in the liver to 25-OH-VitD. 25-OH-VitD represents the main body reservoir and transport form of vitamin D, being stored in adipose tissue and tightly bound by a transport protein while in circulation. A fraction of circulating 25-OH-VitD is converted to its active metabolites 1,25-dihydroxy vitamin D2 and D3 (1,25-OH-VitD), mainly by the kidneys. This process is regulated by parathyroid hormone (PTH), which increases 1,25-OH-VitD synthesis at the expense of the alternative, biologically inactive hydroxylation product 24,25-OH-VitD. Like other steroid hormones, 1,25-OH-VitD binds to a nuclear receptor, ...
This study will compare efficacy and safety of once daily treatment of calcipotriol plus betamethasone dipropionate gel (LEO 80185) with tacalcitol ointment and LEO 80185 vehicle alone in subjects with psoriasis vulgaris. Subjects will be treated for up to 8 weeks followed by an observation period of up to 8 weeks to investigate the occurence and the time to relapse and occurence of rebound after discontinuation of the investigational products. Only subjects with controlled disease will be considered for this observation phase of the study. Controlled disease is defined as Clear or Almost Clear severity category based on Investigators global assessment (IGA ...