Identification and purification of calpactins from cardiac muscle and their effect on Na+/Ca2+ exchange activity.
Calpactins were purified from bovine cardiac muscle by a slightly modified Glenney et al. procedure (J. Cell. Biol. 104, 503-511, 1987). Two major proteins (apparent MW of 36 and 68 kDa) able to bind phospholipids in a Ca2(+)-dependent manner were identified. These proteins completely reversed the inhibition of Na+/Ca2+ exchange activity of cardiac sarcolemmal vesicles consequent to EGTA-treatment. A modulation of cardiac Na+/Ca2+ exchange activity by calpactins is suggested.
Sobota
A
A
Department of Pharmacology, University of Padova, Italy.
Cusinato
F
F
Luciani
S
S
D000818:Animals; D017302:Annexins; D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000302:isolation & purification* / Q000494:pharmacology; D002352:Carrier Proteins / Q000378:metabolism*; D002417:Cattle; D004533:Egtazic Acid / Q000494:pharmacology; D006321:Heart / Q000187:drug effects; D009206:Myocardium / Q000737:chemistry*; D012508:Sarcolemma / Q000737:chemistry* / Q000187:drug effects; D019831:Sodium-Calcium Exchanger
D017302:Annexins; D002135:Calcium-Binding Proteins; D002352:Carrier Proteins; D019831:Sodium-Calcium Exchanger; D004533:Egtazic Acid; D002118:Calcium