John Harmon

Publication Detail

The publication detail shows the title, authors (with indicators showing other profiled authors), information on the publishing organization, abstract and a link to the article in PubMed. This abstract is what is used to create the fingerprint of the publication. If any grants are referenced by the publication, they will be listed here as well.

The effects of proteins on [Ca2+] measurement: different effects on fluorescent and NMR methods.

S Matsuda; H Kusuoka; K Hashimoto; E Tsujimura; T Nishimura (Profiled Author: Hideo Kusuoka)

Division of Tracer Kinetics, Osaka University Medical School, Japan.
Cell calcium 1996;20(5):425-30.

Previous reports showed that the presence of proteins shifts the apparent dissociation constant (Kd) of a fluorescent dye indicator to Ca2+. To elucidate the sensitivity of Kd of an NMR-sensitive Ca2+ indicator, 5-fluoro-1,2-bis(2-amino-phenoxy)ethane N,N,N'N'-tetraacetic acid (5F-BAPTA) to proteins, and compare with that of a dye indicator, Fura-2, we measured Kd of Fura-2 or 5F-BAPTA using Ca-EGTA buffer with or without proteins. Aldolase (ALD) or bovine cardiac protein (BCP) extracted from bovine hearts was used at concentrations of 10, 25, or 50 mg/ml. ALD significantly increased the apparent Kd of Fura-2 to Ca2+ from 164.1 +/- 5.6 nM (mean +/- SE, N = 8) to 757.2 +/- 2.1 nM (n = 4, P < 0.05) at the concentration of 50 mg/ml. In contrast, Kd of 5F-BAPTA was not markedly changed by ALD (298.4 +/- 3. nM without ALD (n = 8), 385.1 +/- 2.7 nM (n = 4) with 50 mg/ml ALD). BCP (50 mg/ml) also significantly increased Kd of Fura-2 (928.5 +/- 3.3 nM, n = 4, P < 0.05), but did not change Kd of 5F-BAPTA (316.0 +/- 2.9 nM, n = 4). These results indicate that Kd of 5F-BAPTA is much less sensitive to the presence of proteins than Fura-2, and that 19F-NMR coupled with 5F-BAPTA is a more robust method to measure intracellular Ca2+ concentration than a fluorescent method with Fura-2.

Scientific Context

This section shows information related to the publication - computed using the fingerprint of the publication - including related publications, related experts and related grants with fingerprints representing significant amounts of overlap between their fingerprint and this publication. The red dots indicate whether those experts or terms appear within the publication, thereby showing potential and actual connections.