Calciotropic hormones and ageing.
Calcium availability is reduced in the elderly because not only of decreased dietary intake of calcium and vitamin D, but also reduced solar exposure and a decrease in the production of provitamin D by the skin. Moreover, calcitriol synthesis and calcitriol activity on calcium absorption by the small intestine are decreased with ageing. The age-related plasma parathormone increase enhances bone remodelling. The decrease of calcitonin secretion in the elderly is possibly related to a loss of sex steroids and calcitriol. 24-hour integrated growth hormone (GH) and insulin-like growth factor I concentrations are also decreased with ageing, but the effectiveness of GH therapy on bone mass in the elderly is still assumed.
Wémeau
J L
JL
Service de Clinique Médicale et d'Endocrinologie, USNA-CHRU, Lille, France.
D000375:Aging / Q000502:physiology*; D002116:Calcitonin / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D013006:Growth Hormone / Q000378:metabolism; D006728:Hormones / Q000502:physiology*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D010281:Parathyroid Hormone / Q000378:metabolism; D014807:Vitamin D / Q000378:metabolism
D006728:Hormones; D010281:Parathyroid Hormone; D014807:Vitamin D; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone; D002116:Calcitonin; D002118:Calcium