title: Subcellular propagation of calcium waves in Müller glia does not require autocrine/paracrine purinergic signaling.
abstract: The polarized morphology of radial glia allows them to functionally interconnect different layers of CNS tissues including the retina, cerebellum, and cortex. A likely mechanism involves propagation of transcellular Ca2+waves which were proposed to involve purinergic signaling. Because it is not known whether ATP release is required for astroglial Ca2+wave propagation we investigated this in mouse Müller cells, radial astroglia-like retinal cells in which in which waves can be induced and supported by Orai/TRPC1 (transient receptor potential isoform 1) channels. We found that depletion of endoplasmic reticulum (ER) stores triggers regenerative propagation of transcellular Ca2+waves that is independent of ATP release and activation of P2X and P2Y receptors. Both the amplitude and kinetics of transcellular, depletion-induced waves were resistant to non-selective purinergic P2antagonists such as pyridoxalphosphate-6-azophenyl-2',4'-disulfonic acid (PPADS). Thus, store-operated calcium entry (SOCE) is itself sufficient for the initiation and subcellular propagation of calcium waves in radial glia.
authors.affiliation: a Department of Ophthalmology & Visual Sciences , University of Utah School of Medicine , Salt Lake City , UT , USA.
authors.forename: Tam T T
authors.initials: TT
authors.lastname: Phuong
authors.affiliation: a Department of Ophthalmology & Visual Sciences , University of Utah School of Medicine , Salt Lake City , UT , USA.
authors.forename: Oleg
authors.initials: O
authors.lastname: Yarishkin
authors.affiliation: a Department of Ophthalmology & Visual Sciences , University of Utah School of Medicine , Salt Lake City , UT , USA.|b Department of Neurobiology & Anatomy , University of Utah School of Medicine , Salt Lake City , UT , USA.|c Department of Bioengineering , University of Utah , Salt Lake City , UT USA.
authors.forename: David
authors.initials: D
authors.lastname: Križaj
mesh_terms: D000818:Animals; D019898:Autocrine Communication; D002118:Calcium / Q000502:physiology*; D020013:Calcium Signaling / Q000502:physiology*; D063928:Ependymoglial Cells / Q000502:physiology*; D005260:Female; D008297:Male; D051379:Mice; D019899:Paracrine Communication
chemical_list: D002118:Calcium
keywords: Ca2+ waves; Müller glia; Orai1; TRPC1; purinergic signaling; store-operated calcium entry