장기간 또는 반복 노출되면 장기(또는, 영향을 받은 알려진 모든 장기를 명시)에 손상을 일으킴
특정 표적장기 독성 - 반복 노출
구분 1
위험
P260, P264, P270, P314, P501
예방조치문구:
P280
보호장갑/보호의/보안경/안면보호구를 착용하시오.
P314
불편함을 느끼면 의학적인 조치·조언을 구하시오.
NFPA 704
0
4
0
VitaMin D4 C화학적 특성, 용도, 생산
개요
Derived from cholesterol, vitamin D is biosynthesized from its prohormone cholecalciferol (D3), the product of
solar ultraviolet irradiation of 7-dehydrocholesterol in the skin.
In 1966, it was first recognized that vitamin
D must undergo activation via two oxidative metabolic steps. The first oxidation to
25-hydroxycholecalciferol (25(OH)D3: calcifediol; Calderol) occurs in the endoplasmic reticulum of the liver and
is catalyzed by vitamin D 25-hydroxylase. This activation step is not
regulated by plasma calcium concentrations. The major circulating form (10–80 μg/mL) is 25(OH)D3, which also
is the primary storage form of vitamin D.
화학적 성질
Pale Yellow Oil
용도
Vitamin D4 is the active analogue of Vitamin D.
Biological Functions
Sterol-specific cytoplasmic receptor proteins (vitamin D receptor) mediate the biological action of vitamin D.
The active hormone is transported from the cytoplasm to the nucleus via the vitamin D receptor, and as a result
of the interaction of the hormone with target genes, a variety of proteins are produced that stimulate the
transport of calcium in each of the target tissues
Active vitamin D works in concert with PTH to enhance active
intestinal absorption of calcium, to stimulate bone resorption, and to prohibit renal excretion of calcium. If
serum calcium or 1,25-calcitriol concentrations are elevated, then vitamin D 24-hydroxylase (in renal
mitochondria) is activated to oxidize 25(OH)D3 to inactive 24,25-dihydroxy-cholecalciferol and to further oxidize
active vitamin D to the inactive 1,24,25-trihydroxylated derivative. Both the 1,24,25-trihydroxylated and the
24,25-dihydroxylated products have been found to suppress PT H secretion as well. The biosynthesis of vitamin D is tightly regulated based on the serum concentrations of calcium, phosphate, PTH, and active vitamin D.
