Interaction of different nucleotides with Ca-release channels from heavy sarcoplasmic reticulum |
| |
| Authors: | A M Rubtsov M B Smirnova A A Boldyrev |
| |
| Institution: | Department of Biochemistry, Moscow State University, U.S.S.R. |
| |
| Abstract: | Calcium accumulation and release from the heavy fraction of sarcoplasmic reticulum vesicles have been studied in the presence of different nucleotides with the use of the Ca-sensitive dye antipyrylazo III for monitoring of the free Ca2+ concentration. The calcium- and caffeine-induced Ca2+ release is observed only with ATP but not with any of nonadenine nucleotides used as substrates for the Ca-pump. Adenine nucleotides provide for a rapid ruthenium red sensitive Ca2+ release from the vesicles, when nonadenine nucleotides are used as energy sources for Ca2+ uptake. A comparison of the nucleotides interaction with Ca-channels and Ca-ATPase supports the hypothesis that Ca-ATPase is involved in the operation of Ca-channels. |
| |
| Keywords: | |
|
|
