Two orientations of isolated cardiac sarcolemmal vesicles separated by affinity chromatography

✍ Scribed by Jaime Mas-Oliva; Alan J. Williams; Winifred G. Nayler

• Book ID: 102983215
• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 667 KB
• Volume: 103
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(80)90259-6

✦ Synopsis

Isolated cardiac sarcolemmal vesicles showing a high degree of purity were separated into two populations of opposite orientation using affinity chromatography. Separations employed the carbohydrate binding characteristics of a wheat germ lectin-Sepharose 6MB column and the location of carbohydrate residues exclusively on the extracellular face of the sarcolemma. The calcium-handling capacities of the two different orientations of vesicle were investigated. Inside-out vesicles showed very low passive binding but high ATPdependent or active transport. In contrast, right-side-out vesicles showed significant passive binding and very little active transport. These results are discussed in terms of the calciumregulating mechanisms of the cardiac muscle cell.