The effect of dietary calcium content and oral vitamin D3 supplementation on mineral homeostasis in a subterranean mole-rat Cryptomys damarensis

Bone Miner. 1994 Nov;27(2):145-57. doi: 10.1016/s0169-6009(08)80216-4.

Abstract

The Damara mole-rat, Cryptomys damarensis, has no access to obvious dietary or endogenous sources of vitamin D. We tested the hypotheses that mineral metabolism in these animals is independent of vitamin D status but rather is affected by dietary calcium (Ca) content. Furthermore, we questioned whether bone and teeth assist in plasma mineral homeostasis. Mole-rats increased Ca intake when dietary Ca content increased; however, mode of gastrointestinal uptake, vitamin D metabolite and plasma Ca concentrations were not altered. Similarly, oral vitamin D supplementation did not affect gastrointestinal Ca absorption or alter plasma Ca concentration, although significant increases in plasma concentrations of vitamin D were evident. Bone and teeth mineral (Ca and Pi) content were augmented with vitamin D supplementation. Mineral homeostasis was primarily maintained by manipulating mineral deposition in teeth, for mineral content in teeth increased significantly when dietary Ca content changed from 1.3 g/kg to 2.6 g/kg and higher. Mineral homeostasis in these subterranean rodents does not appear to be regulated at the level of the intestine, but rather by manipulating bone and teeth mineral reservoirs.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Analysis of Variance
  • Animals
  • Bone Density / physiology*
  • Bone and Bones / metabolism
  • Bone and Bones / physiology*
  • Calcium, Dietary / administration & dosage*
  • Calcium, Dietary / blood
  • Cholecalciferol / administration & dosage*
  • Cholecalciferol / blood
  • Cholecalciferol / metabolism
  • Homeostasis
  • Intestinal Absorption / physiology
  • Phosphorus / blood
  • Rodentia
  • Spectrophotometry, Atomic
  • Tooth / metabolism
  • Tooth / physiology*

Substances

  • Calcium, Dietary
  • Cholecalciferol
  • Phosphorus