Spontaneous calcium release from sarcoplasmic reticulum. Effect of local anesthetics. Export

@article{citeulike:4728712, abstract = {Spontaneous calcium release from purified light sarcoplasmic reticulum has been previously described (Palade, P., Mitchell, R. D., and Fleischer, S. (1983) J. Biol. Chem. 258, 8098-8107) and found to be distinct from several other forms of Ca2+ release. Ca2+ release occurs after a lag period following active Ca2+ preloading and depletion of extravesicular Ca2+. In the present study, we find that local anesthetics inhibit spontaneous Ca2+ release, in a time-dependent manner, varying considerably in the preincubation time required to exert maximal effect. At pH 7.0, hydrophilic and mostly charged local anesthetics, such as procaine, procainamide, and N-(2,6-dimethylphenyl carbamoyl methyl)triethyl ammonium bromide, inhibit Ca2+ release only after long preincubations (hours), whereas more hydrophobic local anesthetics are effective after only a short incubation (minutes) with sarcoplasmic reticulum. The more hydrophobic anesthetics take somewhat longer to reach equilibrium, as studied by inhibition of unidirectional Ca2+ efflux, and there is a direct relationship between hydrophobic partition coefficient and half-time to reach equilibrium. Agents known to inhibit permeability pathways for monovalent cations i.e. K+ channel blockers (decamethonium and n-dodecane-1, 12-N,N,N,N',N',N'-hexamethyl-bis-ammonium) or the anion blocker (4,4'-diisothiocyanostilbene-2,2'-disulfonic acid), do not inhibit spontaneous Ca2+ release. Carbonyl cyanide m-fluorophenylhydrazone, a protonophore, and gramicidin D, a monovalent cation ionophore, have no effect on Ca2+ release whether local anesthetics are present or not, while the Ca2+ ionophore A23187 relieves inhibition of Ca2+ release by local anesthetics. Ruthenium red does not inhibit spontaneous Ca2+ release. These findings suggest that the binding site(s) for local anesthetics is located on the inner face of the sarcoplasmic reticulum membrane and that local anesthetics interact directly with a Ca2+ channel rather than with other permeability pathways which might indirectly influence Ca2+ channel gating.}, author = {Volpe, P. and Palade, P. and Costello, B. and Mitchell, R. D. and Fleischer, S.}, citeulike-article-id = {4728712}, citeulike-linkout-0 = {http://view.ncbi.nlm.nih.gov/pubmed/6630192}, citeulike-linkout-1 = {http://www.hubmed.org/display.cgi?uids=6630192}, day = {25}, issn = {0021-9258}, journal = {The Journal of biological chemistry}, keywords = {fast, fraction, light, muscle, reticulum, sarcoplasmic, skeletal, sr, tetracaine, twitch}, month = {October}, number = {20}, pages = {12434--12442}, posted-at = {2009-06-03 04:59:45}, priority = {2}, title = {Spontaneous calcium release from sarcoplasmic reticulum. Effect of local anesthetics.}, url = {http://view.ncbi.nlm.nih.gov/pubmed/6630192}, volume = {258}, year = {1983} }

TY - JOUR ID - citeulike:4728712 L3 - citeulike-article-id:4728712 N2 - Spontaneous calcium release from purified light sarcoplasmic reticulum has been previously described (Palade, P., Mitchell, R. D., and Fleischer, S. (1983) J. Biol. Chem. 258, 8098-8107) and found to be distinct from several other forms of Ca2+ release. Ca2+ release occurs after a lag period following active Ca2+ preloading and depletion of extravesicular Ca2+. In the present study, we find that local anesthetics inhibit spontaneous Ca2+ release, in a time-dependent manner, varying considerably in the preincubation time required to exert maximal effect. At pH 7.0, hydrophilic and mostly charged local anesthetics, such as procaine, procainamide, and N-(2,6-dimethylphenyl carbamoyl methyl)triethyl ammonium bromide, inhibit Ca2+ release only after long preincubations (hours), whereas more hydrophobic local anesthetics are effective after only a short incubation (minutes) with sarcoplasmic reticulum. The more hydrophobic anesthetics take somewhat longer to reach equilibrium, as studied by inhibition of unidirectional Ca2+ efflux, and there is a direct relationship between hydrophobic partition coefficient and half-time to reach equilibrium. Agents known to inhibit permeability pathways for monovalent cations i.e. K+ channel blockers (decamethonium and n-dodecane-1, 12-N,N,N,N',N',N'-hexamethyl-bis-ammonium) or the anion blocker (4,4'-diisothiocyanostilbene-2,2'-disulfonic acid), do not inhibit spontaneous Ca2+ release. Carbonyl cyanide m-fluorophenylhydrazone, a protonophore, and gramicidin D, a monovalent cation ionophore, have no effect on Ca2+ release whether local anesthetics are present or not, while the Ca2+ ionophore A23187 relieves inhibition of Ca2+ release by local anesthetics. Ruthenium red does not inhibit spontaneous Ca2+ release. These findings suggest that the binding site(s) for local anesthetics is located on the inner face of the sarcoplasmic reticulum membrane and that local anesthetics interact directly with a Ca2+ channel rather than with other permeability pathways which might indirectly influence Ca2+ channel gating. IS - 20 JF - The Journal of biological chemistry SN - 0021-9258 EP - 12442 TI - Spontaneous calcium release from sarcoplasmic reticulum. Effect of local anesthetics. VL - 258 SP - 12434 KW - fast KW - fraction KW - light KW - muscle KW - reticulum KW - sarcoplasmic KW - skeletal KW - sr KW - tetracaine KW - twitch AU - Volpe, P AU - Palade, P AU - Costello, B AU - Mitchell, RD AU - Fleischer, S PY - 1983/10/25/ UR - http://view.ncbi.nlm.nih.gov/pubmed/6630192 ER -