HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Nohmi, M. Articles by Hua, S. Y. Search for Related Content PubMed PubMed Citation Articles by Nohmi, M. Articles by Hua, S. Y. Social Bookmarking                      What's this?

J. Biol. Chem., Vol. 266, Issue 33, 22254-22259, 11, 1991

Ultraviolet light activates blocking actions of dantrolene on intracellular Ca2+ release in bullfrog sympathetic neurones

M Nohmi, K Kuba and SY Hua
Department of Physiology, Saga Medical School, Japan.

Effects of dantrolene, a blocker of intracellular Ca2+ release, on the oscillation of the intracellular Ca2+ ([Ca2+]i) induced by caffeine were studied in bullfrog sympathetic ganglion cells, using a Fura-2 fluorescence technique. Dantrolene blocked the Ca2+ oscillation only in the cell illuminated by ultraviolet light (335-385 nm). Likewise, the blocking effects on rhythmic Ca(2+)-dependent hyperpolarizations, representing Ca2+ oscillations via activation of Ca(2+)-dependent K+ channel, occurred only under the illumination with ultraviolet light (335-385 nm), but not with visible light (404-417 nm). This wavelength dependence differs from the absorbance spectrum of dantrolene. On the other hand, dantrolene preirradiated with ultraviolet light under dark condition or ultraviolet light itself did not affect the [Ca2+]i oscillation. The blocking action was not prevented by the pretreatment of the cells with reducing agents. These results indicate that illumination of the Ca2+ release channel or dantrolene itself with ultraviolet light (possibly the former) is necessary for the drug to exert its blocking effect. Furthermore, dantrolene was found to decrease Fura-2 fluorescence and to increase cell autofluorescence, leading sometimes to a false decrease in the basal [Ca2+]i.
CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    What's this?

This article has been cited by other articles:

				K. Motoyama, I. E. Karl, M. W. Flye, D. F. Osborne, and R. S. Hotchkiss Effect of Ca2+ agonists in the perfused liver: determination via laser scanning confocal microscopy Am J Physiol Regulatory Integrative Comp Physiol, February 1, 1999; 276(2): R575 - R585. [Abstract] [Full Text] [PDF]