dihydrotachysterol and Skin-Diseases

Calciphylaxis is a local tissue calcific reaction at the site of an injection of challenger substance given a critical time period after the oral administration of a sensitizer substance such as dihydrotachysterol (DHT), vitamin D or parathormone. Cutaneous calciphylaxis is readily induced in the rat but not in the mouse and this may be because, in the latter, the challenger substance is absorbed rapidly by macrophages. In the rat the administration of 500 micrograms/0.1 ml of DHT followed after 24 h by the subcutaneous (SC) injection of ferric chloride (FeCl3) (30 micrograms/0.1 ml) is followed rapidly by calcification of the SC site. There is an early transient acute inflammatory reaction with the incrustation of collagen fibres by the iron salt and an apparent exudation of calcium and phosphate ions from the bloodstream. These ions also become associated with collagen fibres. Two days after injection macrophages and multinucleated giant cells become the dominant cells. Calciphylaxis is a useful experimental model of ectopic calcification and is associated with an initial hypercalcaemia. The diphosphonates ethane-1-hydroxy-1, 1-diphosphonate (EHDP) and dichloromethylene diphosphonate (Cl2MDP) are effective inhibitors of the calciphylactic reaction when administered prior to the initiation of the experimental procedure.

Topics: Animals; Calcinosis; Calciphylaxis; Chlorides; Clodronic Acid; Dihydrotachysterol; Diphosphonates; Dose-Response Relationship, Drug; Etidronic Acid; Female; Ferric Compounds; Macrophages; Mice; Muscles; Rats; Skin Diseases

The amount of non-collagenous proteins is increased greatly during the pathological calcification of rat skin experimentally induced by dihydrotachysterol (DHT) and Ovalbumin (topical cutaneous calciphylaxis). This is accompanied by an increase in the total amount and concentrations of protein-bound serine phosphate [Ser(P)], threonine phosphate [Thr(P)] and gamma-carboxyglutamic acid (Gla), almost all of which can be extracted from the tissue and can be dissociated from collagen in 0.5M EDTA. The EDTA-soluble, non-collagenous proteins are rich in aspartic and glutamic acids, similar to the non-collagenous, EDTA-soluble proteins of bone, cementum and calcified cartilage, and quite distinct from those of dentin and enamel.

Topics: 1-Carboxyglutamic Acid; Animals; Calciphylaxis; Dihydrotachysterol; Disease Models, Animal; Female; Glutamates; Ovalbumin; Phosphoserine; Phosphothreonine; Rats; Serine; Skin; Skin Diseases; Threonine

Topics: Adenosine Triphosphate; Animals; Calcinosis; Cell Membrane Permeability; Collagen; Dihydrotachysterol; Glycosaminoglycans; Hypercalcemia; Rats; Skin Diseases

Topics: Animals; Aortic Diseases; Calcinosis; Dihydrotachysterol; Estradiol; Kidney Diseases; Organophosphonates; Phloretin; Phosphates; Phosphoric Monoester Hydrolases; Rats; Skin Diseases

Topics: Animals; Autoradiography; Calciphylaxis; Chlorides; Dihydrotachysterol; Female; Glycosaminoglycans; Histocytochemistry; Injections, Subcutaneous; Iron; Phosphates; Rats; Skin Diseases; Time Factors

Topics: Animals; Arsenicals; Calcinosis; Dermatitis, Contact; Dihydrotachysterol; Dimethyl Sulfoxide; Dinitrophenols; Eczema; Female; Guinea Pigs; Hemorrhage; Hypersensitivity; Necrosis; Rats; Skin Diseases

Topics: Animals; Calcinosis; Calcium; Dihydrotachysterol; Disease Models, Animal; Female; Glycosaminoglycans; Histocytochemistry; Rats; Scleroderma, Systemic; Skin Diseases

Topics: Animals; Apatites; Calcinosis; Calciphylaxis; Collagen; Dihydrotachysterol; Microscopy, Electron; Rats; Skin Diseases

Topics: Animals; Calcinosis; Calciphylaxis; Dihydrotachysterol; Necrosis; Phosphates; Rats; Skin Diseases; X-Ray Diffraction

Topics: Calcinosis; Calciphylaxis; Calcium; Calcium, Dietary; Dihydrotachysterol; Iron-Dextran Complex; Lead; Nephrocalcinosis; Pathology; Polymyxins; Rats; Research; Skin Diseases; Toxicology

Topics: Calcinosis; Dermatology; Dihydrotachysterol; Hypercalcemia; Nephrocalcinosis; Pathology; Rats; Research; Skin Diseases; Toxicology

Topics: Adipose Tissue; Alopecia; Aortic Diseases; Atrophy; Calcinosis; Cockayne Syndrome; Coronary Disease; Dihydrotachysterol; Emaciation; Kidney Diseases; Kyphosis; Muscular Atrophy; Osteosclerosis; Pathology; Pharmacology; Progeria; Rats; Research; Sex; Sex Characteristics; Skin Diseases; Tooth Abnormalities; Toxicology

Topics: Alkaline Phosphatase; Calcinosis; Clinical Enzyme Tests; Collagen; Dihydrotachysterol; Egg White; Fibroblasts; Glycosaminoglycans; Histocytochemistry; Hyaluronic Acid; Iron-Dextran Complex; Mast Cells; Pathology; Rats; Research; Skin Diseases; Toxicology

Topics: Calcinosis; Calcium; Dihydrotachysterol; Phosphorus; Phosphorus, Dietary; Skin Diseases; Vitamin D; Vitamins

Topics: Calcification, Physiologic; Calcinosis; Dihydrotachysterol; Skin Diseases

Topics: Calcinosis; Dihydrotachysterol; Skin Diseases

Topics: Calcinosis; Dihydrotachysterol; Humans; Scleroderma, Systemic; Sclerosis; Skin Diseases