Note
IO ret% muscles such as the cardiac and the skeletaI, myoglobiu plays au esserrtiai role iu maiutaiuiug aerobic metabolism, both as au oxygeu store and by faciiitatmg oxygeu diffusion la. When these museies suffer from ischemia or other injuries causing cell destruction, the soluble myoglobin wiJ.l be c!eared into blood with myoglobmemia aud even into uriue with myoglobimuk The very sensitive quantitation of myoglobin in serum and uriue can therefore provide an important new diagnostic test for acute myocardial iufXction as well as for other muscular dkases, such as crush syndrome, progressive muscular dystrophy and polymyositis.
In respouse to the recent increasing ueed for highIy purified human myoglobiu for mdioimmuuoassa~ and enzyme immuaoassa~, this commu&atior; deals with the isolation and chamcterization of oxymyoglobiu fern human muscle.
In contrast to the cIassical preparations of myogiobin in the met-form6-lo, modern procedures for isolating oxymyogiobm directly from muscle tissues all stem from the method of Shikama and co-worker@. This has been improved with some refiuemeats and controls using bovine heart muscle, a more readily available sourc~P-~~.
KQ work described iu this report, essemially the same procedure was successfuHy applied for isolating oxymyoglobin from human muscle for the fkst time.. Myogiobin was extracted overnight at pM 8.0 from the miuced, partially tbawed mu&e (1 kg) of human psoas with 1.5 volumes of cold disti&d water. The muscle was obtained at autopsy from adult patients who died of uou-muscular disorders and was stored at -5ยฐC by the First Departmeut of luterual Medicine, Tohoku University School of Mediciue, Send& Ah procedures were carried out at low temperature (04ยฐC) as far as possible. The iusoiubte material was removed by ceutilgation at 3GJOg for 10 miu, and the supernatane was decauted through a doubled gauze cloth to remove fatty substauces. This extract was then fkactionated with ammouium sulphate betweeu 60 and laO% saturation at pH 7.0 iu the presence of 5 10-' M EDTA The ptipitate was-ceutrifuged at 30,4X0 g for 15 miu and dissolved in a miuimum vohuue of 5 m&ZTris-HCl buffer @El 8.4)). The solution was theu dialyzed agaiust ffie same buffer containing 5-lo-' M EDNA. The crude myoglobm solution (ce, 500 ml), which still contaiued a large amount of hemoglobiu, was applied to four Sephadex G-50 cohuuus (Pharmacia, UppsaEa, Sweden; flue, 98 x 5cm I.D.) ecpil-