Details

Autor(en) / Beteiligte

• Chu, Alice
• Dixon, Mark C.
• Saito, Akitsugu
• Seiler, Steven
• Fleischer, Sidney

Titel

[4] Isolation of sarcoplasmic reticulum fractions referable to longitudinal tubules and functional terminal cisternae from rabbit skeletal muscle

Ist Teil von

• Methods in Enzymology, 1988, Vol.157, p.36-46

Ort / Verlag

Elsevier Science & Technology

Erscheinungsjahr

1988

Link zum Volltext

Beschreibungen/Notizen

• This chapter focuses on the isolation of sarcoplasmic reticulum fractions referable to longitudinal tubules and junctional terminal cistemae from rabbit skeletal muscle. The sarcoplasmic reticulum (SR) of fast skeletal muscle fibers is a sleeve-like network surrounding the myofibrils that controls the cytoplasmic calcium concentration and—thereby, regulates muscle contraction and relaxation. The membranous system consists of mainly two regions: (1) Tubular longitudinal elements and (2) bulbous terminal cisternae. The latter is junctionally associated with the tranverse tubule via bridging structures referred to as “feet.” Recently, the preparation of a highly enriched SR fraction of junctional terminal cisternae with morphologically intact feet structures has been reported. The isolation procedures for small-land large-scale preparations are described in the chapter. The small-scale preparation uses swinging bucket rotors, while the large-scale preparation uses zonal rotors. SR microsomes are first isolated by homogenization of muscle and differential centrifugation. Fast skeletal muscle from the hind legs of three rabbits is used. The selection of predominantly white muscle and homogenization of ground muscle are carried out as described above for the small-scale preparation to the supernatant (SUP) step.