Regulation of the mechano sensitive cation channels by ATP and cAMP in leech neurons

Year: 2006

Authors: Barsanti C., Pellegrini M., Pellegrino M.

Autors Affiliation: Dipartimento di Fisiologia e Biochimica G. Moruzzi, Università di Pisa, Via S. Zeno 31, 56127, Pisa, Italy; Scuola Normale Superiore, piazza Cavalieri 7, 56126, Pisa, Italy

Abstract: Single-channel recordings were used to study the modulation of stretch-activated channels (SACs) by intracellular adenosine nucleotides in identified leech neurons. These channels exhibited two activity modes, spike-like (SL) and multiconductance (MC), displaying different polymodal activation. In the absence of mechanical stimulation, internal perfusion of excised patches with ATP induced robust and reversible activation of the MC but not of the SL mode. The ATP effect on channel activity was dose-dependent within a range of 1 mu M -1 mM and was induced at different values of intracellular pH and Ca2+. The non-hydrolyzable ATP analog AMP-PNP, ATP without Mg2+ or ADP also effectively enhanced MC activity. Adenosine mimicked the effect of its nucleotides. At negative membrane potentials, both ATP and adenosine activated the channel. Moreover, ATP but not adenosine induced a flickering block. Addition of cAMP during maximal ATP activation completely and reversibly inhibited the channel, with activation and deactivation times of minutes. However, cAMP alone only induced a weak and rapid channel activation, without inhibitory effects. The expression of these channels in the growth cones of leech neurons, their permeability to Ca2+ and their sensitivity to intracellular cAMP are consistent with a role in the Ca2+ oscillations associated with cell growth. (c) 2006 Elsevier B.V. All rights reserved.

Journal/Review: BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES

Volume: 1758 (5)      Pages from: 666  to: 672

KeyWords: mechanosensitive ion channel; patch-clamp; single-channel recording; TRP channel; modulation
DOI: 10.1016/j.bbamem.2006.03.013

ImpactFactor: 3.587
Citations: 6
data from “WEB OF SCIENCE” (of Thomson Reuters) are update at: 2024-11-10
References taken from IsiWeb of Knowledge: (subscribers only)

Connecting to view paper tab on IsiWeb: Click here
Connecting to view citations from IsiWeb: Click here