[Calciotropic actions of parathyroid hormone and vitamin D-endocrine system].
Parathyroid hormone (PTH) and 1,25-dihydroxyvitamin D [1,25-(OH)zD] participate in systemic regulation of calcium homeostasis through endocrine effects mediated via the specific receptors PTHR1 and VDR, expressed in bone, kidney, intestine and parathyroid glands. In bone, both hormones PTH and 1,25-(OH)2D promote calcium release into the circulation; however, they also have anabolic effects in this tissue. In kidney, PTH controls 1,25-(OH)2D synthesis, and together both hormones stimulate calcium reabsorption. The most important calciotropic action of 1,25-(OH)2D is stimulation of intestinal calcium absorption. In the parathyroid glands, 1,25-(OH)2D regulates PTH synthesis through a negative feedback mechanism, while modulating the gland growth. Finally, a general overview of the maternal adaptations regarding calcium homeostasis during pregnancy and lactation is presented.
Avila
Euclides
E
Departamento de Biología de la Reproducción, Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán, Tlalpan, DF México. euclides@quetzal.innsz.mx
Barrera
David
D
Díaz
Lorenza
L
D000818:Animals; D001842:Bone and Bones / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D002136:Calcium, Dietary / Q000493:pharmacokinetics; D025461:Feedback, Physiological; D005260:Female; D006706:Homeostasis; D006801:Humans; D007408:Intestinal Absorption / Q000502:physiology; D007421:Intestine, Small / Q000378:metabolism; D007686:Kidney Tubules, Distal / Q000378:metabolism; D007774:Lactation / Q000502:physiology; D008322:Mammals / Q000378:metabolism; D051379:Mice; D010280:Parathyroid Glands / Q000254:growth & development / Q000378:metabolism; D010281:Parathyroid Hormone / Q000502:physiology*; D011247:Pregnancy; D014807:Vitamin D / Q000031:analogs & derivatives* / Q000502:physiology
D002136:Calcium, Dietary; D010281:Parathyroid Hormone; D014807:Vitamin D; C097949:1,25-dihydroxyvitamin D; D002118:Calcium