Photo-released intracellular Ca2+ evokes reversible mechanical responses in supporting cells of the guinea-pig organ of Corti.
Biochemical and Biophysical Research Communications. 1994-06-01; 201(3): 1263-1269
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1. Biochem Biophys Res Commun. 1994 Jun 30;201(3):1263-9.
Photo-released intracellular Ca2+ evokes reversible mechanical responses in
supporting cells of the guinea-pig organ of Corti.
Dulon D(1), Blanchet C, Laffon E.
(1)1-Laboratoire d’Audiologie Expérimentale, Inserm et Université de Bordeaux II,
Hôpital Pellegrin, France.
Loaded under whole cell patch-clamp configuration, the caged Ca2+ molecule
DM-nitrophen was used to increase [Ca2+]i rapidly and reversibly in isolated
Deiters cells of the organ of Corti. Photolysis of DM-nitrophen increased [Ca2+]i
from resting concentrations of 20-50 nM to values above microM, as measured with
the fluorescent indicator Fluo-3. Immediately after the photoliberation of Ca2+,
a movement of the head of the phalangeal process could be observed in 75% of
cells (n = 28). This mechanical movement, with an amplitude ranging between 0.5
to 1 micron within few hundred of ms, consisted of an extension of the phalanges
away from the cell body. Measurement of phalangeal stiffness in transversal
flexion toward the cell body ranged between 15-440 pN/micron. Stiffness can
increase by 28 to 51% after rising [Ca2+]i. The results suggest Ca2+ as a
potential intracellular messenger for active mechanical responses in Deiters
PMID: 8024570 [Indexed for MEDLINE]