1 alpha-hydroxy-25-fluorovitamin D3: a potent analogue of 1 alpha,25-dihydroxyvitamin D3. 1978

J L Napoli, and M A Fivizzani, and H K Schnoes, and H F DeLuca

Chemically synthesized 1 alpha-hydroxy-25-fluorovitamin D3 was compared to 1,25-dihydroxyvitamin D3 for potency in the chick intestinal cytosol-binding protein assay, induction of intestinal calcium transport, mobilization of calcium from bone, and epiphyseal plate calcification in the rat. The 25-fluorinated analogue causes 50% displacement of 1,25-dihydroxy[23,24-3H]D3 at 1.8 X 10(-8) M in the competitive protein-binding assay, whereas only 5.6 X 10(-11) M of unlabeled 1,25-dihydroxyvitamin D3 is needed for equal competition. This 315-fold difference between and 1 alpha-hydroxy-25-fluorovitamin D3 indicates that the fluoro analogue is about equipotent with 1 alpha-hydroxyvitamin D3 in the protein-binding assay. However, 1 alpha-hydroxy-25-fluorovitamin D3 is 1/50 as active as 1,25-dihydroxyvitamin D3 in vivo in the stimulation of intestinal calcium transport and bone calcium mobilization in vitamin D deficient rats on a low-calcium diet. Likewise, 1 alpha-hydroxy-25-fluorovitamin D3 is about 40 times less active than 1,25-dihydroxyvitamin D3 in inducing endochondrial calcification in rachitic rats. No selective actions of 1alpha-hydroxy-25-fluorovitamin D3 were noted. Since the 25 position of the analogue is blocked by a fluorine atom, it appears that 25-hydroxylation of 1 alpha-hydroxylated vitamin D compounds in vivo is not an obligatory requirement for appreciable vitamin D activity.

UI MeSH Term Description Entries
D007413 Intestinal Mucosa Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI. Intestinal Epithelium,Intestinal Glands,Epithelium, Intestinal,Gland, Intestinal,Glands, Intestinal,Intestinal Gland,Mucosa, Intestinal
D008297 Male Males
D011485 Protein Binding The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments. Plasma Protein Binding Capacity,Binding, Protein
D001842 Bone and Bones A specialized CONNECTIVE TISSUE that is the main constituent of the SKELETON. The principal cellular component of bone is comprised of OSTEOBLASTS; OSTEOCYTES; and OSTEOCLASTS, while FIBRILLAR COLLAGENS and hydroxyapatite crystals form the BONE MATRIX. Bone Tissue,Bone and Bone,Bone,Bones,Bones and Bone,Bones and Bone Tissue,Bony Apophyses,Bony Apophysis,Condyle,Apophyses, Bony,Apophysis, Bony,Bone Tissues,Condyles,Tissue, Bone,Tissues, Bone
D002113 Calcification, Physiologic Process by which organic tissue becomes hardened by the physiologic deposit of calcium salts. Bone Mineralization,Calcification, Physiological,Physiologic Calcification,Mineralization, Bone,Physiological Calcification
D002118 Calcium A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes. Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D002645 Chickens Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA. Gallus gallus,Gallus domesticus,Gallus gallus domesticus,Chicken
D006887 Hydroxycholecalciferols Hydroxy analogs of vitamin D 3; (CHOLECALCIFEROL); including CALCIFEDIOL; CALCITRIOL; and 24,25-DIHYDROXYVITAMIN D 3. Hydroxyvitamins D,Hydroxycholecalciferol
D000818 Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA. Animal,Metazoa,Animalia
D001667 Binding, Competitive The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements. Competitive Binding

Related Publications

J L Napoli, and M A Fivizzani, and H K Schnoes, and H F DeLuca
October 1979, Archives of biochemistry and biophysics,
J L Napoli, and M A Fivizzani, and H K Schnoes, and H F DeLuca
October 1989, Journal of nutritional science and vitaminology,
J L Napoli, and M A Fivizzani, and H K Schnoes, and H F DeLuca
February 1985, Chemical & pharmaceutical bulletin,
J L Napoli, and M A Fivizzani, and H K Schnoes, and H F DeLuca
December 1980, Biochemical and biophysical research communications,
J L Napoli, and M A Fivizzani, and H K Schnoes, and H F DeLuca
April 1988, Immunology letters,
J L Napoli, and M A Fivizzani, and H K Schnoes, and H F DeLuca
March 1983, Biochemistry,
Copied contents to your clipboard!