 |
ARTICLE |
|---|
Top
Article
|
|---|
The purpose of the Perspectives in General Physiology is to provide a forum where scientific uncertainties or controversies can be discussed in an authoritative, yet open manner.
The Perspectives are solicited by the editors
often based on recommendations by the advisory editors or members of the editorial board, who may be asked to coordinate the process. To frame the issue, two or more experts
will be invited to present a brief point of view on the problem, which will be published back-to-back in The Journal.
These Perspectives will be accompanied by one or two editorial paragraphs that introduce the problemand invite the submission of comments, in the form of letters to the editor, which will be published in a single, predetermined
issue (usually four months after publication of the Perspectives). The letters may be no longer than two printed
pages (approximately six double-spaced pages) and will be subject to editorial review. They may contain no more
than one figure, and may not contain significant references to unpublished work. After the letters to the editor
have been published, further responses will be limited to full manuscripts.
This issue of The Journal contains three perspectives on calcium sparks, by Schneider, by Cannell and Soeller, and by Shirokova et al. Calcium sparks, first described in 1993, are transient localized increases in fluorescence that can be detected in cardiac and skeletal muscle fibers loaded with a calcium indicator such as fluo-3. The calcium responsible for spark fluorescence is released from a single SR calcium channel or a small group of channels that behaves as a source of minute volume, <1 µm3. Calcium sparks are of interest because they are expected to provide information about local regulation of calcium release through only a few (perhaps even one) SR calcium channels. Moreover, under certain circumstances, at least in frog muscle, macroscopic SR calcium release appears to represent the spatial and temporal summation of many sparks. As shown in the following perspectives, important information has been obtained about the properties of calcium sparks and of the SR calcium release that produces them. In spite of this progress, however, disagreement remains about properties as basic as the mean amplitude of a calcium spark and of the underlying calcium flux. The search for this and other information is expected to keep the sparkologists bright and active for some time to come.
Letters to the editor related to this topic will be published in the July 1999 issue of The Journal of General Physiology. Letters to the editor should be received no later than May 1, 1999, to allow for the editorial review. Letters can be submitted electronically, by sending a formatted text file as an attachment in an e-mail to the editorial office: jgp{at}rockvax.rockefeller.edu Figures must be submitted in hardcopy (they can be faxed so that they are received in the editorial office by the May 1 deadline).
