Metabolic Studies on Vitamin D

History of the discovery of vitamin D and its active metabolites

“…36 Thus, it was assumed from this point on that vitamin D itself functioned without metabolic change, an idea that was to persist until 1968. 37 The discovery of vitamin D resulted in a variety of attempts to understand how this steroid might result in the healing of rickets and its adult counterpart, osteomalacia. One of the early experiments that is often unappreciated are the studies of Shipley et al 38,39 in which slices of bone taken from rachitic animals were incubated in the blood serum of vitamin D-deficient animals or in the blood serum of animals provided with vitamin D. The provisional deposit of calcium and phosphate was found in the case of bone slices incubated in serum of animals that had been given vitamin D. However, the addition of vitamin D to the serum of vitamin D-deficient rats did not in any way influence the deposit of mineral in the bone.…”

“…37 Professor Kodicek laboriously prepared radiolabeled vitamin D 2 by incubating Discovery of vitamin D HF DeLuca yeast in 14 C containing acetate medium. He was successful in obtaining vitamin D 2 of fairly low specific activity to begin his studies on metabolism.…”

“…He was successful in obtaining vitamin D 2 of fairly low specific activity to begin his studies on metabolism. Kodicek 37 had attempted to study metabolism without the use of radiolabels and found it laborious and difficult to interpret. After more than a decade of experimentation, Kodicek 58 concluded that vitamin D was active directly without metabolic change, as all metabolites were found without biological activity.…”

TRIENNIAL GROWTH SYMPOSIUM— Vitamin D: Bones and beyond12

“…Between 1930 and 1949, the chemical change that occurs to 7-dehydrocholesterol in response to 280 to 315 nm UV light was elucidated by the work of Havinga (1973) and of Velluz et al (1949). Until 1968, the idea that vitamin D directly acted to heal rickets remained intact (Kodicek, 1956). One of the well-established functions of vitamin D is to increase the ability of the intestine to absorb calcium and phosphorus (Nicolaysen, 1937;Nicolaysen et al, 1953), which are the 2 major components needed to mineralize the skeleton.…”

Η Επιδραση Της 1α-Υδροξυβιταμινης D3 Στον Ανθεκτικο Υποφωσφαταιμικο Ραχιτισμο

“…'Η χορήγηση της βιταμίνης D σέ μεγάλες δόσεις είναι χρήσιμη στό νά προλά βει τό δευτεροπαθή ύπερπαραθυρεοειδισμό πού προκαλείται άπό τή χορήγηση τοϋ φωσφόρου , Teitelibaum et al 1976 (Peterson 1971). Ή βιταμίνη D απορ ροφάται πολύ καλά από τό έντερο (Kodicek et al 1956). Εί ναι γνωστό ότι γιά την απορρόφηση της βιταμίνης D απαιτεί ται ή παρουσία χολικών αλάτων (Greaves and Schimidt 1933).…”