Vitamin D Flashcards
Who discovered that after destroying the vitamin A content of cod liver oil by oxidation, it still possessed ability to cure rickets?
McCollum
Who received the ultra-violet patent at U.W.
Steenbock
Vitamin D promotes ___ and ___ absorption
Ca and P
-synthesis of a Ca-binding protein
-increase permeability of mucosal cells to Ca and P
Where is and what is Ca and P absorbed as?
in the intestine as vit. D
-25-OH D in the liver
-1,25-(OH)2 in kidney
Vitamin D is thought of as a ______
hormone
Active form is made by the ____
kidney
Active form travels to act on the _____ and ______
bones and intestines
Vitamin D is required for normal ________
calcification
-amount varies with Ca and P amounts and ratio of Ca/P
Highest requirements of vit. D are needed for:
-young and lactating animals
-swine and poultry
-wide Ca and P ratios
What other two hormones are involved in calcification?
-calcitonin (lowers blood Ca levels and puts Ca back into bone)
-PTH (raises blood Ca levels and takes Ca out of bone)
Rickets
disturbance of Ca and P metabolism - poor calcification of bones (occurs in young)
Pigeon-breast
softening of bones in the chest, bowing of the chest
Osteomalacia
failure of the bone matrix to become mineralized
-if mother is deficient possible congenital malformations
-importance of D to adults
Where is vit. D primarily stored?
in liver
-no large transfer to fetus
-not as great ability to store as vit. A
Vitamin D deficiency in chickens
-thin egg shells
-decreased hatchability
-decreased egg production
