Vitamin D Dependence of In Vivo Calcium Transport and Mucosal Calcium Binding Protein in Rat Large Intestine

1979 ◽  
Vol 76 (1) ◽  
pp. 99-104 ◽  
Author(s):  
M. Michael Petith ◽  
Helen D. Wilson ◽  
Harold P. Schedl
Keyword(s):  
Vitamin D ◽  
Large Intestine ◽  
Calcium Binding ◽  
Calcium Transport ◽  
Binding Protein ◽  
Calcium Binding Protein

Calcium absorption and intestinal calcium-binding protein: quantitative relationship.

1979 ◽  
Vol 236 (5) ◽  
pp. E556 ◽  
Author(s):  
J J Feher ◽  
R H Wasserman
Keyword(s):  
Vitamin D ◽  
Vitamin D3 ◽  
Calcium Binding ◽  
Calcium Absorption ◽  
Binding Protein ◽  
Quantitative Relationship ◽  
Calcium Binding Protein ◽  
Vitamin D Status ◽  
Loop Technique

The concentration of the vitamin D-induced calcium-binding protein (CaBP) and calcium absorption from the duodenum were investigated in chicks with an in vivo ligated-loop technique. The relation between CaBP and calcium absorption was dependent on a) source of vitamin D activity (either vitamin D3 or 1,25-dihydroxycholecalciferol); b) dosage of vitamin D3; c) time after administration of vitamin D3 to rachitic animals. To aid in the interpretation of these results, a phenomenological model was developed in which CaBP was viewed as being linearly related to a portion of calcium absorption. The model, when applied to the data, suggests that there is a "nonfunctional" pool of CaBP the size of which is determined by the vitamin D status of the animal. After correction for this nonfunctional pool, the proportionality between CaBP and calcium absorption is independent of the vitamin D status of the animal.

scholarly journals Calcium-binding protein of the chick chorioallantoic membrane. II. Vitamin K-dependent expression

1978 ◽  
Vol 77 (3) ◽  
pp. 752-761 ◽  
Author(s):  
RS Tuan ◽  
WA Scott ◽  
ZA Cohn
Keyword(s):  
Vitamin D ◽  
Vitamin K ◽  
Calcium Binding ◽  
Binding Protein ◽  
Vitamin K Antagonists ◽  
Chorioallantoic Membrane ◽  
Calcium Binding Protein ◽  
Simple Method ◽  
Chick Chorioallantoic Membrane

A simple method was devised for the maintenance of the chorioallantoic membrane (CAM) of chick embryos in organ culture. Explants of CAM survived for up to 5 days in this system and retained the characteristic three-layered morphology (ectoderm, mesoderm, and endoderm). Induction of the CAM calcium-binding protein (CaBP) by effectors of calcium metabolism was studied in these organ cultures. Vitamin K was found to elicit a seven- to eightfold increase in CaBP, whereas no increase in CaBP activity occurred on supplementation with vitamin A, parathyroid hormone, an analogue of vitamin D, vitamin D and its hydroxylated metabolites, or with elevated calcium levels. The vitamin K-mediated induction of CaBP was dose-dependent, inhibited by the vitamin K antagonists warfarin and dicoumarol, selective for vitamin K5, and maximal at the developmental stage (13-15 days of incubation) corresponding to the onset of calcium transport by the CAM in vivo. CaBP levels increased after 60-70 h in cultures of 13-15 day CAM supplemented with vitamin K and reached maximal levels around 80-90 h of culture. The CAM ectoderm underwent extensive proliferation and often assumed a villuslike morphology in the vitamin K cultures.

Intestinal vitamin D-induced calcium-binding protein: time-course of immunocytological localization following 1,25-dihydroxyvitamin D3.

1983 ◽  
Vol 31 (3) ◽  
pp. 426-432 ◽  
Author(s):  
A N Taylor
Keyword(s):  
Vitamin D ◽  
Calcium Binding ◽  
Calcium Transport ◽  
Time Course ◽  
Binding Protein ◽  
Calcium Binding Protein ◽  
Dihydroxyvitamin D3 ◽  
Migration Rates ◽  
1,25 Dihydroxyvitamin D3 ◽  
Free Cells

The vitamin D-induced calcium-binding protein (CaBP) was localized in histological sections of chick duodenum using the peroxidase-antiperoxidase immunocytochemical technique. The time-course of appearance of CaBP in rachitic chicks was investigated from 0 to 120 hr after stimulation by 1,25-dihydroxyvitamin D3 (1,25(OH)2D3). CaBP was not routinely detected at 0 hr after 1,25(OH)2D3 administration. CaBP was first noted in some, but not all, of the samples taken 2 hr following 1,25(OH)2D3 and was detected in all 2 1/2 hr samples. The number of CaBP-containing absorptive cells and the apparent CaBP concentration both increased to a maximum at about 16-24 hr. At later times, as CaBP free cells migrated up the villi, the CaBP-containing cells decreased in number, but even at 120 hr post 1,25(OH)2D3 dose there were significant numbers of CaBP-containing cells present. The relationships between time-course of CaBP location on intestinal villi, enterocyte migration rates, and the time-course of 1,25(OH)2D3 stimulated intestinal calcium transport are discussed.

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