creatine kinase

クレアチンキナーゼ CK

WordNet

1. an amino acid that does not occur in proteins but is found in the muscle tissue of vertebrates both in the free form and as phosphocreatine; supplies energy for muscle contraction (同)creatin
2. an enzyme that catalyzes the conversion of a proenzyme to an active enzyme
3. the basic unit of money in Papua New Guinea

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/12/11 01:37:22」(JST)

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Creatine kinase
Crystal structure of Human Brain-type Creatine Kinase with ADP and creatine. PDB 3b6r.
Identifiers
EC number	2.7.3.2
CAS number	9001-15-4
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Gene Ontology	AmiGO / EGO
Search PMC articles PubMed articles NCBI proteins

Creatine kinase (CK), also known as creatine phosphokinase (CPK) or phospho-creatine kinase (and sometimes incorrectly as creatinine kinase), is an enzyme (EC 2.7.3.2) expressed by various tissues and cell types. CK catalyses the conversion of creatine and consumes adenosine triphosphate (ATP) to create phosphocreatine (PCr) and adenosine diphosphate (ADP). This CK enzyme reaction is reversible and thus ATP can be generated from PCr and ADP.

In tissues and cells that consume ATP rapidly, especially skeletal muscle, but also brain, photoreceptor cells of the retina, hair cells of the inner ear, spermatozoa and smooth muscle, PCr serves as an energy reservoir for the rapid buffering and regeneration of ATP in situ, as well as for intracellular energy transport by the PCr shuttle or circuit. Thus creatine kinase is an important enzyme in such tissues.

Clinically, creatine kinase is assayed in blood tests as a marker of myocardial infarction (heart attack), rhabdomyolysis (severe muscle breakdown), muscular dystrophy, the autoimmune myositides and in acute renal failure.

Types

In the cells, the "cytosolic" CK enzymes consist of two subunits, which can be either B (brain type) or M (muscle type). There are, therefore, three different isoenzymes: CK-MM, CK-BB and CK-MB. The genes for these subunits are located on different chromosomes: B on 14q32 and M on 19q13. In addition to those three cytosolic CK isoforms, there are two mitochondrial creatine kinase isoenzymes, the ubiquitous and sarcomeric form. The functional entity of the latter two mitochondrial CK isoforms is an octamer consisting of four dimers each.

While mitochondrial creatine kinase is directly involved in formation of phospho-creatine from mitochondrial ATP, cytosolic CK regenerates ATP from ADP, using PCr. This happens at intracellular sites where ATP is used in the cell, with CK acting as an in situ ATP regenerator.

gene	protein
CKB	creatine kinase, brain, BB-CK
CKBE	creatine kinase, ectopic expression
CKM	creatine kinase, muscle, MM-CK
CKMT1A, CKMT1B	creatine kinase mitochondrial 1; ubiquitous mtCK; or umtCK
CKMT2	creatine kinase mitochondrial 2; sarcomeric mtCK; or smtCK

Isoenzyme patterns differ in tissues. CK-BB is expressed in all tissues at low levels and has little clinical relevance.^{[citation needed]} Skeletal muscle expresses CK-MM (98%) and low levels of CK-MB (1%). The myocardium (heart muscle), in contrast, expresses CK-MM at 70% and CK-MB at 25–30%.

Functions

The mitochondrial creatine kinase (CK_m) is present in the mitochondrial intermembrane space, where it produces phosphocreatine (PCr) from mitochondrially generated ATP and creatine (Cr) imported from the cytosol. Apart from the two mitochondrial CK isoenzyme forms, that is, ubiquitous mtCK (present in non-muscle tissues) and sarcomeric mtCK (present in sarcomeric muscle), there are three cytosolic CK isoforms present in the cytosol, depending on the tissue. Whereas MM-CK is expressed in sarcomeric muscle, that is, skeletal and cardiac muscle, MB-CK is expressed in cardiac muscle, and BB-CK is expressed in smooth muscle and in most non-muscle tissues. Mitochondrial mtCK and cytosolic CK are connected in a so-called PCr/Cr-shuttle or circuit. PCr generated by mtCK in mitochondria is shuttled to cytosolic CK that is coupled to ATP-dependent processes, e.g. ATPases, like acto-myosin ATPase for muscle contraction, or ion pumps, like the calcium pump for muscle relaxation. There, the bound cytosolic CK accepts the PCr shuttled through the cell and uses it to regenerate ATP, which can then be used as energy source by the ATPases. (CK is associated intimately with the ATPases, forming a functionally coupled microcompartment.) Thus, PCr is not only an energy buffer but also a cellular transport form of energy between subcellular sites of energy (ATP) production (mitochondria and glycolysis) and those of energy utilization (ATPases).

Laboratory testing

CK is often determined routinely in a medical laboratory. It is also determined specifically in patients with chest pain or if acute renal failure is suspected. Normal values are usually between 60 and 174 IU/L, where one unit is enzyme activity, more specifically the amount of enzyme that will catalyze 1 μmol of substrate per minute under specified conditions (temperature, pH, substrate concentrations and activators. This test is not specific for the type of CK that is elevated.

Elevation of CK is an indication of damage to muscle. It is therefore indicative of injury, rhabdomyolysis, myocardial infarction, myositis and myocarditis. The use of statin medications, which are commonly used to decrease serum cholesterol levels, may be associated with elevation of the CPK level in about 1% of the patients taking these medications, and with actual muscle damage in a much smaller proportion.

There is an inverse relationship in the serum levels of T3 and CK in thyroid disease. In hypothyroid patients, with decrease in serum T3 there is a significant increase in CK. Therefore, the estimation of serum CK is considered valuable in screening for hypothyroid patients.

Lowered CK can be an indication of alcoholic liver disease and rheumatoid arthritis.

Isoenzyme determination has been used extensively as an indication for myocardial damage in heart attacks. Troponin measurement has largely replaced this in many hospitals, although some centers still rely on CK-MB.

Reference ranges for blood tests, comparing blood content of creatine kinase (shown in yellow near center) with other constituents.

CK can be used in the diagnosis of neuroleptic malignant syndrome, which is manifested as fever, rigidity, altered mental state and autonomic dysfunction.

See also

• Kinase
• Reference ranges for blood tests

References

External links

• Simply stated at mdausa.org
• Creatine Kinase at the US National Library of Medicine Medical Subject Headings (MeSH)
• CPK isoenzymes test MedlinePlus Encyclopedia 003504
• CK at Lab Tests Online

UpToDate Contents

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• 1. 神経筋疾患の評価における筋酵素muscle enzymes in the evaluation of neuromuscular diseases [show details]
  … myopathies. Thus, serum creatine kinase (CK) activity >1000 units/L helps to distinguish muscle disease from neurogenic causes of weakness and muscle atrophy. More modest elevation of CK may occur in some primary …
• 2. 横紋筋融解症の臨床症状および診断clinical manifestations and diagnosis of rhabdomyolysis [show details]
  … kidney injury; We obtain the following key diagnostic laboratory studies: Creatine kinase – Fractionation of the creatine kinase (CK) is generally not required but may be helpful, in addition to the clinical …
• 3. 腎不全患者における血清酵素serum enzymes in patients with renal failure [show details]
  …hospital and/or coronary care units. The principal cardiac enzymes are the MB isoenzyme of creatine kinase (CK-MB), cardiac troponin T, and cardiac troponin I . Since coronary artery disease is highly …
• 4. Perioperative advanced cardiac life support (ACLS)perioperative advanced cardiac life support acls [show details]
  …abnormalities that include respiratory and possibly metabolic acidosis, hyperkalemia, elevated creatine kinase, and serum and urine myoglobin. Details regarding treatment are present in the table and in a…
• 5. 腎不全患者における血清心臓バイオマーカーserum cardiac biomarkers in patients with renal failure [show details]
  …isoenzyme of creatine kinase (CK-MB) is not the preferred biomarker but can still be used in the absence of cardiac troponin assays. This topic reviews the clinical use of cardiac troponins and CK-MB in patients …

English Journal

• Ectopic overexpression of porcine DGAT1 increases intramuscular fat content in mouse skeletal muscle.

• Li T, Xu D, Zuo B, Lei M, Xiong Y, Chen H, Zhou Y, Wu X.SourceKey Laboratory of Swine Genetics and Breeding, Ministry of Agriculture and Key Laboratory of Agriculture Animal Genetics, Breeding and Reproduction, Ministry of Education, College of Animal Science, Huazhong Agricultural University, Wuhan, 430070, China.
• Transgenic research.Transgenic Res.2013 Feb;22(1):187-94. doi: 10.1007/s11248-012-9633-z. Epub 2012 Jul 24.
• The microsomal enzyme 1, 2-acyl CoA: diacylglyceroltransferase-1 (DGAT1) plays an important role in triglyceride storage in adipose tissue and expresses in skeletal muscle as well. The primary goal of the present study was to investigate the effect of porcine DGAT1 on intramuscular fat (IMF) content
• PMID 22826105

• Antiophidic activity of the extract of the Amazon plant Humirianthera ampla and constituents.

• Strauch MA, Tomaz MA, Monteiro-Machado M, Ricardo HD, Cons BL, Fernandes FF, El-Kik CZ, Azevedo MS, A Melo P.SourcePrograma de Pós-Graduação em Farmacologia e Química Medicinal, Instituto de Ciências Biomédicas, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Avenida Brigadeiro Trompowski, Rio de Janeiro, RJ 21941-590, Brazil.
• Journal of ethnopharmacology.J Ethnopharmacol.2013 Jan 9;145(1):50-8. doi: 10.1016/j.jep.2012.10.033. Epub 2012 Nov 1.
• ETHNOPHARMACOLOGICAL RELEVANCE: Although serotherapy against snakebite has been discovered more than one hundred years ago, antivenom is not available all over Brazil. The use of plants from folk medicine is common mainly in the Brazilian Amazon area. One of these plants is named Humirianthera ampla
• PMID 23123799

Japanese Journal

• Involvement of the phosphatidylinositol kinase pathway in augmentation of ATP-sensitive K+ channel currents by hypo-osmotic stress in rat ventricular myocytes

• Mitsuyama Hirofumi,Yokoshiki Hisashi,Irie Yuki,Watanabe Masaya,Mizukami Kazuya,Tsutsui Hiroyuki
• Canadian journal of physiology and pharmacology 91(9), 686-692, 2013-09-00
• … Augmentation of I-K,I-ATP during hypo-osmotic stress was attenuated by wortmannin (50 mu mol/L), an inhibitor of phosphatidylinositol 3- and 4-kinases, but not by (i) phalloidin (30 mu mol/L), an actin filament stabilizer, (ii) the absence of Ca2+ from the internal and external solutions, and (iii) the presence of creatine phosphate (3 mmol/L), which affects creatine kinase regulation of the K-ATP channels. …
• NAID 120005333605

• 縦隔奇形種を合併した福山型先天性筋ジストロフィーの1例

• 梶野 幸子,石垣 景子,島田 姿野,西川 愛子,伊藤 進,唐木 克二,川島 章子,土屋 晶義,村上 てるみ,佐藤 孝俊,齊藤 崇,西川 俊郎,世川 修,大澤 真木子,KAJINO Sachiko,ISHIGAKI Keiko,SHIMADA Shino,NISHIKAWA Aiko,ITO Susumu,KARAKI Katsuji,KAWASHIMA Shoko,TSUCHIYA Masayoshi,MURAKAMI Terumi,SATO Takatoshi,SAITO Takashi,NISHIKAWA Toshio,SEGAWA Osamu,OSAWA Makiko
• 東京女子医科大学雑誌 83(E1), E358-E361, 2013-01-31
• 福山型先天性筋ジストロフィー(Fukuyama congenital muscular dystrophy: FCMD)は,fukutin(FKTN)遺伝子変異により,重度の筋ジストロフィー病変に眼病変,中枢神経系の形成障害を伴う全身性疾患である.本邦の小児型筋ジストロフィーではDuchenne型に次いで多い.経過中,縦隔奇形腫を合併した軽症FCMDの一女児例を経験したので報告する.症例は3歳2か …
• NAID 110009559398

• 福山型先天性筋ジストロフィーにおける発熱性疾患罹患後の筋力低下増悪に対する治療の検討

• 村上 てるみ,石垣 景子,佐藤 孝俊,梶野 幸子,齊藤 崇,大澤 真木子,MURAKAMI Terumi,ISHIGAKI Keiko,SATO Takatoshi,KAJINO Sachiko,SAITO Takashi,OSAWA Makiko
• 東京女子医科大学雑誌 83(E1), E36-E41, 2013-01-31
• 福山型先天性筋ジストロフィー(FCMD)は大脳形成異常、精神遅滞を特徴とする先天性筋ジストロフィーで、責任遺伝子はα-ジストログリカンの糖鎖付加に関与するFKTN遺伝子である。,私たちは以前、FCMD患者がウイルス感染による発熱性疾患罹患後に、高クレアチンキナーゼ(CK)血症や尿中ミオグロビン高値を伴い、時に呼吸不全から死に至る急激な筋力低下の増悪を呈することを報告した。これまでの報告では、発症時 …
• NAID 110009559369

Related Links

• Creatine kinaseとは - goo Wikipedia (ウィキペディア)

Creatine kinase From Wikipedia, the free encyclopedia Jump to: navigation, search Creatine kinase Crystal structure of Human Brain-type Creatine Kinase with ADP and creatine. PDB 3b6r. [1] Identifiers EC number 2.7.3.2 CAS ...

• クレアチンキナーゼ【creatine kinase】の意味 - 国語辞書 - goo辞書

クレアチンキナーゼ【creatine kinase】とは。意味や解説。骨格筋や心筋などの細胞に存在し、クレアチンリン酸の合成・分解を触媒する酵素。筋肉の収縮時にはクレアチンリン酸をクレアチンとリン酸に分解し、ADPにリン酸基を転移して ...

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★リンクテーブル★

リンク元	「クレアチンキナーゼ」「CK」
拡張検索	「BB form creatine kinase」「creatine kinase-MM isoform」「creatine kinase assay」
関連記事	「kinase」

「クレアチンキナーゼ」

　　[★]

英

creatine kinase CK

同

クレアチンホスホキナーゼ creatine phosphokinase CPK, phosphokinase

関

クレアチン

基準値

• 39-238 U/L

測定原理

• Oliver-Rosalki法
• クレアチンキナーゼの逆反応により生じたATPをNADPHの340nmにおける吸光度増加として測定する初速度測定法 (臨床検査法提要第32版 p.605)

ATP + glucose　←(ヘキソキナーゼ)→glucose-6-phosphate + ADP

glucose-6-phosphate + NADP⁺ ←(G-6-PD)→ 6-phosphogluconate + NADPH + H⁺

「CK」

　　[★] クレアチンキナーゼ creatine kinase

「BB form creatine kinase」

　　[★]

クレアチンキナーゼBB

関

creatine kinase BB

「creatine kinase-MM isoform」

　　[★] クレアチンキナーゼMM・アイソフォーム

「creatine kinase assay」

　　[★] クレアチンキナーゼ測定法

「kinase」

　　[★] キナーゼ カイネース リン酸化酵素 phosphoenzyme phosphotransferase