药品详细
Vitamin A(维生素A)
化学结构式图
中文名
维生素A
英文名
Vitamin A
分子式
C20H30O
化学名
3,7-dimethyl-9-(2,6,6-trimethylcyclohex-1-en-1-yl)nona-2,4,6,8-tetraen-1-ol
分子量
Average: 286.4516
Monoisotopic: 286.229665582
Monoisotopic: 286.229665582
CAS号
68-26-8
ATC分类
A11C 未知;D10A Anti-Acne Preparations for Topical Use;S01X 其他眼科用药;R01A 未知
药物类型
small molecule
阶段
approved, nutraceutical
商品名
同义名
基本介绍
Retinol and derivatives of retinol that play an essential role in metabolic functioning of the retina, the growth of and differentiation of epithelial tissue, the growth of bone, reproduction, and the immune response. Dietary vitamin A is derived from a variety of carotenoids found in plants. It is enriched in the liver, egg yolks, and the fat component of dairy products. [PubChem]
生产厂家
- Arcum pharmaceutical corp
- Astrazeneca lp
- Banner pharmacaps inc
- Bayer pharmaceuticals corp
- Bel mar laboratories inc
- Bristol myers squibb co
- Chase chemical co lp
- Del ray laboratories inc
- Eli lilly and co
- Elkins sinn div ah robins co inc
- Everylife
- Hospira inc
- Impax laboratories inc
- Ivax pharmaceuticals inc sub teva pharmaceuticals usa
- Mk laboratories inc
- Sterling winthrop inc
- Teva pharmaceuticals usa inc
- West ward pharmaceutical corp
- Wharton laboratories inc div us ethicals
封装厂家
- Ambix Labs
- A-S Medication Solutions LLC
- AstraZeneca Inc.
- Breckenridge Pharmaceuticals
- Bristol-Myers Squibb Co.
- Dispensing Solutions
- Dofs Laboratories
- Ethex Corp.
- Freeda Vitamins
- Gerber Products Co.
- Gordon Pharmacy
- Hi Tech Pharmacal Co. Inc.
- Hospira Inc.
- Laboratorios Magnachem International SA
- Magno-Humphries Laboratories
- Major Pharmaceuticals
- Mucos Emulsion GmbH
- Nextwave Pharmaceuticals Inc.
- Pharmedix
- Physicians Total Care Inc.
- Qualitest
- River's Edge Pharmaceuticals
- Sancilio and Company Inc.
- Spectrum Pharmaceuticals
- Teral Laboratories
- Tris Pharma Inc.
- Vintage Pharmaceuticals Inc.
参考
| Synthesis Reference | Not Available |
| General Reference |
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剂型
规格
化合物类型
| Type | small molecule |
| Classes |
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| Substructures |
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适应症
药理
| Indication | For the treatment of vitamin A deficiency. |
| Pharmacodynamics | Vitamin A is effective for the treatment of Vitamin A deficiency. Vitamin A refers to a group of fat-soluble substances that are structurally related to and possess the biological activity of the parent substance of the group called all-trans retinol or retinol. Vitamin A plays vital roles in vision, epithelial differentiation, growth, reproduction, pattern formation during embryogenesis, bone development, hematopoiesis and brain development. It is also important for the maintenance of the proper functioning of the immune system. |
| Mechanism of action | Vision:Vitamin A (all-trans retinol) is converted in the retina to the 11-cis-isomer of retinaldehyde or 11-cis-retinal. 11-cis-retinal functions in the retina in the transduction of light into the neural signals necessary for vision. 11-cis-retinal, while attached to opsin in rhodopsin is isomerized to all-trans-retinal by light. This is the event that triggers the nerve impulse to the brain which allows for the perception of light. All-trans-retinal is then released from opsin and reduced to all-trans-retinol. All-trans-retinol is isomerized to 11-cis-retinol in the dark, and then oxidized to 11-cis-retinal. 11-cis-retinal recombines with opsin to re-form rhodopsin. Night blindness or defective vision at low illumination results from a failure to re-synthesize 11-cis retinal rapidly. Epithelial differentiation: The role of Vitamin A in epithelial differentiation, as well as in other physiological processes, involves the binding of Vitamin A to two families of nuclear retinoid receptors (retinoic acid receptors, RARs; and retinoid-X receptors, RXRs). These receptors function as ligand-activated transcription factors that modulate gene transcription. When there is not enough Vitamin A to bind these receptors, natural cell differentiation and growth are interrupted. |
| Absorption | Readily absorbed from the normal gastrointestinal tract |
| Volume of distribution | Not Available |
| Protein binding | <5% of circulating vitamin A is bound to lipoproteins in blood in normal condition, but may be up to 65% when hepatic stores are saturated because of excessive intake. When released from liver, vitamin A is bound to retinol-binding protein (RBP). Most vitamin A circulates in the form of retinol bound to RBP. |
| Metabolism |
Hepatic. Retinol is conjugated with glucuronic acid; the B-glucuronide undergoes enterohepatic circulation and oxidation to retinol and retinoic acid. Retinoic acid undergoes decarboxylation and conjugation with glucuronic acid.
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| Route of elimination | Not Available |
| Half life | 1.9 hours |
| Clearance | Not Available |
| Toxicity | Acute toxicity (single ingestion of 7 500 RE or 25 000 IU per kg or more): Signs and symptoms may be delayed for 8 to 24 hours and include: increased intracranial pressure, headache, irritability, drowsiness, dizziness, lethargy, vomiting, diarrhea, bulging of fontanels in infants, diplopia, papilledema. Peeling of skin around mouth may be observed from 1 to several days after ingestion and may spread to the rest of the body. Chronic, excessive ingestion (1 200 RE or 4 000 IU/kg daily for 6 to 15 months) may produce symptoms of pseudotumor cerebri, anorexia, weakness, arthralgias, bone pain, bone demineralization, dry skin, cracked lips, brittle nails, hair loss, splenomegaly, hepatomegaly, hypoplastic anemia, leukopenia, optic neuropathy, and blindness. Increased plasma concentrations of vitamin A occur but do not necessarily correlate with toxicity. |
| Affected organisms |
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| Pathways | Not Available |
理化性质
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| State | solid | ||||||||||||||||||||||||||||||||||||||||||
| Experimental Properties |
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| Predicted Properties |
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药物相互作用
| Drug | Interaction |
|---|---|
| Acitretin | Acitretin increases the risk of vitamin A toxicity. Avoid vitamin A supplementation while taking acitretin. |
| Bexarotene | Bexarotene increases the risk of vitamin A toxicity. Avoid vitamin A supplementation while taking bexarotene. |
| Isotretinoin | Isotretinoin increases the risk of vitamin A toxicity. Avoid vitamin A supplementation while taking isotretinoin. |
| Orlistat | Orlistat may impair the absorption of vitamin A, a fat soluble vitamin. Oral vitamin A should be administered 2 hours prior to or post orlistat administration. |
| Tretinoin | Tretinoin increases the risk of vitamin A toxicity. Avoid vitamin A supplementation while taking systemic tretinoin. |
食物相互作用
Not Available
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