Abstract
Flash photolysis of DM-nitrophen generates an extremely large [Ca2+] transient ("Ca2+ spike") at the start of each Ca2+ "step." The Ca2+ spike greatly increases the speed of activation of the ryanodine receptor channel ("supercharging") and could be responsible for apparent channel adaptation.
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Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Armstrong C. M., Chow R. H. Supercharging: a method for improving patch-clamp performance. Biophys J. 1987 Jul;52(1):133–136. doi: 10.1016/S0006-3495(87)83198-3. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chu A., Fill M., Stefani E., Entman M. L. Cytoplasmic Ca2+ does not inhibit the cardiac muscle sarcoplasmic reticulum ryanodine receptor Ca2+ channel, although Ca(2+)-induced Ca2+ inactivation of Ca2+ release is observed in native vesicles. J Membr Biol. 1993 Jul;135(1):49–59. doi: 10.1007/BF00234651. [DOI] [PubMed] [Google Scholar]
- Fill M., Coronado R., Mickelson J. R., Vilven J., Ma J. J., Jacobson B. A., Louis C. F. Abnormal ryanodine receptor channels in malignant hyperthermia. Biophys J. 1990 Mar;57(3):471–475. doi: 10.1016/S0006-3495(90)82563-7. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Györke S., Fill M. Response. Science. 1994 Feb 18;263(5149):987–988. doi: 10.1126/science.263.5149.987. [DOI] [PubMed] [Google Scholar]
- Györke S., Fill M. Ryanodine receptor adaptation: control mechanism of Ca(2+)-induced Ca2+ release in heart. Science. 1993 May 7;260(5109):807–809. doi: 10.1126/science.8387229. [DOI] [PubMed] [Google Scholar]
- Györke S., Vélez P., Suárez-Isla B., Fill M. Activation of single cardiac and skeletal ryanodine receptor channels by flash photolysis of caged Ca2+. Biophys J. 1994 Jun;66(6):1879–1886. doi: 10.1016/S0006-3495(94)80981-6. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Lamb G. D. Ca2+ inactivation, Mg2+ inhibition and malignant hyperthermia. J Muscle Res Cell Motil. 1993 Dec;14(6):554–556. doi: 10.1007/BF00141551. [DOI] [PubMed] [Google Scholar]
- Lamb G. D., Fryer M. W., Stephenson D. G. Ca(2+)-induced Ca2+ release in response to flash photolysis. Science. 1994 Feb 18;263(5149):986–988. doi: 10.1126/science.8310298. [DOI] [PubMed] [Google Scholar]
- Ma J., Fill M., Knudson C. M., Campbell K. P., Coronado R. Ryanodine receptor of skeletal muscle is a gap junction-type channel. Science. 1988 Oct 7;242(4875):99–102. doi: 10.1126/science.2459777. [DOI] [PubMed] [Google Scholar]
- McCray J. A., Fidler-Lim N., Ellis-Davies G. C., Kaplan J. H. Rate of release of Ca2+ following laser photolysis of the DM-nitrophen-Ca2+ complex. Biochemistry. 1992 Sep 22;31(37):8856–8861. doi: 10.1021/bi00152a023. [DOI] [PubMed] [Google Scholar]
- Meissner G., Darling E., Eveleth J. Kinetics of rapid Ca2+ release by sarcoplasmic reticulum. Effects of Ca2+, Mg2+, and adenine nucleotides. Biochemistry. 1986 Jan 14;25(1):236–244. doi: 10.1021/bi00349a033. [DOI] [PubMed] [Google Scholar]
- Moisescu D. G. Kinetics of reaction in calcium-activated skinned muscle fibres. Nature. 1976 Aug 12;262(5569):610–613. doi: 10.1038/262610a0. [DOI] [PubMed] [Google Scholar]
- Zucker R. S. The calcium concentration clamp: spikes and reversible pulses using the photolabile chelator DM-nitrophen. Cell Calcium. 1993 Feb;14(2):87–100. doi: 10.1016/0143-4160(93)90079-l. [DOI] [PubMed] [Google Scholar]