dihydrotachysterol and Body-Weight

Fourteen patients with pseudohypoparathyroidism, 17 with idiopathic hypoparathyroidism, and 12 with postoperative hypoparathyroidism were treated with vitamin D2, dihydrotachysterol, 1 alpha-hydroxyvitamin D3)1 alpha-OHD3), and 1,25-dihydroxyvitamin D3 for 6-18 months. The optimal maintenance dose or minimum daily dose of 1,25-dihydroxyvitamin D3 to maintain serum calcium at approximately 8.5 mg/100 ml and control all the clinical symptoms was 1.3 +/- 0.16 micrograms/day (mean +/- SE) in pseudohypoparathyroidism, 1.5 +/- 0.18 micrograms/day in idiopathic hypoparathyroidism, and 1.9 +/- 0.50 micrograms/day in postoperative hypoparathyroidism. There was no significant difference in the optimal maintenance dose among the 3 groups. The optimal maintenance dose of 1 alpha-OHD3, however, was 2.0 +/- 0.12 micrograms/day in pseudohypoparathyroidism, significantly lower than that in idiopathic hypoparathyroidism (3.5 +/-0.29 micrograms/day; P less than 0.001) and in postoperative hypoparathyroidism (4.89 +/- 0.54 micrograms/day; P less than 0.001). Significantly lower doses were required in the treatment of idiopathic hypoparathyroidism than in postoperative hypoparathyroidism (P less than 0.05). No significant difference was found in the optimal maintenance dose of dihydrotachysterol and vitamin D2 among the 3 groups. The average pretreatment serum calcium levels and clinical manifestations were indistinguishable among the 3 groups of patients. This suggests that such a difference in the optimal maintenance dose of 1 alpha-OHD3 is ascribed not to the difference in the severity of hypoparathyroidism, but most probably to differences in the pathophysiological processes in pseudohypoparathyroidism and idiopathic or postoperative hypoparathyroidism. The excess parathyroid hormone levels in blood of patients with pseudohypoparathyroidism (and not in other types of hypoparathyroidism) may explain such a difference.

Topics: Adolescent; Adult; Aged; Body Weight; Calcifediol; Calcitriol; Calcium; Dihydrotachysterol; Ergocalciferols; Female; Humans; Hydroxycholecalciferols; Hypoparathyroidism; Male; Middle Aged; Parathyroid Hormone; Phosphorus; Postoperative Complications; Pseudohypoparathyroidism; Vitamin D

Interest in the pharmacological effects of drugs in the elderly has created a need for a laboratory model in which responses of aged animals to drugs can be studied. Dihydrotachysterol (DHT)-induced progeria, a syndrome with symptoms similar to those seen in normal aging, was evaluated as an old age model. DHT-treatment was shown to produce a decreased carbohydrate tolerance that was due to an impaired release of insulin from pancreatic islets and not due to a decreased sensitivity to insulin. These changes were unlike those observed with aging. Thus, DHT-induced progeria would not appear to be a good model for aging for the investigation of carbohydrate metabolism. Evidence is presented which indicates that glucose and tolbutamide act via different mechanism to stimulate insulin release.

Topics: Aging; Animals; Body Weight; Carbohydrate Metabolism; Dihydrotachysterol; Eating; Glucose; Insulin; Male; Models, Biological; Progeria; Rats; Time Factors; Tolbutamide

Aortic medial calcification was investigated in rats in which the progeria-like syndrome (PLS) was evoked by administering dihydrotachysterol. In 35 experimental rats and 15 controls, calcification was studied morphologically by light and electron microscopy, and by enzyme histochemistry. Body weight, food intake and serum calcium levels were also determined. Calcification occurred along and on the elastic lamellae in association with the accumulation of ground substance. In the smooth-muscle cells surrounding the calcified foci, the activities of various lysosomal enzymes increased concomitantly with a tendency toward transformation of smooth-muscle cells to a modified form. From these observations, the role of ground-substance formation by smooth-muscle cells is postulated, and participation in the catabolism of ground substance by the lysosomal enzymes of these cells is suggested. It appears the increased activity of adenosine monophosphatase should be linked to the calcification. The etiology of weight loss, skin manifestations and aortic calcification in PLS rats seems to be different from that in human progeric diseases. Therefore, the PLS rat should not be readily accepted as an animal model for the study of progeric diseases.

Topics: Acid Phosphatase; Adenosine Triphosphatases; Animals; Aorta; Aortic Diseases; Apyrase; Body Weight; Calcinosis; Calcium; Dihydrotachysterol; Female; Glucuronidase; Hexosaminidases; Histocytochemistry; Phosphoric Monoester Hydrolases; Rats; Werner Syndrome

Topics: Adolescent; Anticonvulsants; Body Height; Body Weight; Calcium; Child; Dihydrotachysterol; Epilepsy, Tonic-Clonic; Ergocalciferols; Humans; Hypocalcemia; Hypoparathyroidism; Male; Middle Aged; Osteomalacia; Rickets; Time Factors; Ultraviolet Therapy; Vitamin D

Topics: Administration, Oral; Animals; Appetite; Body Weight; Calcium; Calcium Carbonate; Diet; Dihydrotachysterol; Female; Femur; Oils; Rats; Time Factors

Topics: Animals; Basal Metabolism; Body Weight; Dihydrotachysterol; Female; Hypophysectomy; Hypothalamo-Hypophyseal System; Rats; Stimulation, Chemical; Thyroid Gland; Thyrotropin; Thyroxine

Topics: Animals; Body Weight; Calcium; Dihydrotachysterol; Environmental Exposure; Hot Temperature; Male; Rats; Thyrotropin; Thyroxine

Topics: Alkaline Phosphatase; Animals; Body Weight; Bone and Bones; Calcium; Collagen; Connective Tissue; Dihydrotachysterol; Hydroxyproline; Methyltestosterone; Phosphorus; Rats

Topics: Analysis of Variance; Animals; Body Weight; Bone Resorption; Calcium; Diet; Dihydrotachysterol; Ergocalciferols; Hypercalcemia; Intestinal Absorption; Kidney; Magnesium; Phosphorus; Rats; Rats, Inbred Strains; Stomach; Tibia; Time Factors

Topics: Animals; Aorta; Body Weight; Calcium; Castration; Dihydrotachysterol; Estrogens; Female; Femur; Kidney; Myocardium; Organ Size; Progeria; Rats

Topics: Animals; Aorta; Body Weight; Calcinosis; Calcium; Dihydrotachysterol; Estrogens, Conjugated (USP); Female; Femur; Hypercalcemia; Kidney; Organ Size; Osteoporosis; Progeria; Rats; Tail

Topics: Acetates; Adrenalectomy; Age Factors; Aldosterone; Animals; Body Weight; Connective Tissue; Corticosterone; Depression, Chemical; Desoxycorticosterone; Dihydrotachysterol; Epiphyses; Estradiol; Female; Femur; Guinea Pigs; Hormones; Hydrocortisone; Male; Mice; Prednisolone; Progesterone; Rabbits; Rats; Sex Factors; Spironolactone; Stimulation, Chemical; Stress, Physiological; Succinates; Tail; Tendons; Testosterone

Topics: Animals; Basophils; Body Weight; Bone Marrow; Bone Marrow Examination; Dihydrotachysterol; Eosinophils; Leukocyte Count; Leukocytes; Neutrophils; Progeria; Rats

Topics: Animals; Body Weight; Bone and Bones; Calcium; Chickens; Cholecalciferol; Dichlorodiphenyldichloroethane; Dihydrotachysterol; Ergocalciferols; Liver; Male; Phosphorus; Rickets; Tibia; Vitamin D

Topics: Aging; Animals; Animals, Newborn; Aortic Diseases; Arteriosclerosis; Blood; Body Weight; Calcinosis; Coronary Disease; Dihydrotachysterol; Female; Hypercalcemia; In Vitro Techniques; Kidney Diseases; Lactation; Pregnancy; Pregnancy, Animal; Rats

Topics: Biomedical Research; Body Weight; Calciphylaxis; Calcium; Calcium, Dietary; Deficiency Diseases; Diet; Dihydrotachysterol; Iron; Pathology; Phosphates; Rats; Research; Skin; Toxicology