%0 Journal Article %9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES %A Sauviat, M.P. %A Boydron Le Garrec, Raphaëlle %A Masson, J.B. %A Lewis, R.L. %A Vernoux, J.P. %A Molgo, J. %A Laurent, Dominique %A Benoit, E. %T Mechanisms involved in the swelling of erythrocytes caused by Pacific and Caribbean ciguatoxins %D 2006 %L fdi:010051883 %G ENG %J Blood Cells Molecules and Diseases %@ 1079-9796 %K ciguatoxins ; red blood cells ; cell swelling ; L type Ca2+ channels ; nitric oxide ; nitric oxide synthase ; soluble guanylate cyclase ; cytochalasin D %M CC:0002348800-0001 %N 1 %P 1-9 %R 10.1016/j.bcmd.2005.10.007 %U https://www.documentation.ird.fr/hor/fdi:010051883 %> https://www.documentation.ird.fr/intranet/publi/depot/2011-06-01/010051883.pdf %V 36 %W Horizon (IRD) %X The mechanisms underlying the swelling of frog red blood cells (RBC), induced by Pacific (P-CTX-1) and Caribbean (C-CTX-1) ciguatoxins (CTXs), were investigated by measuring the length, width and surface of their elliptic shape. P-CTX-1 (0.5 to 5 nM) and C-CTX-1 (1 mu M) induced RBC swelling within 60 min. The CTXs-induced RBC swelling was blocked by apamin (1 mu M) and by Sr2+ (1 mu M). P-CTX-1-induced RBC swelling was prevented and inhibited by H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one(27 mu M), an inhibitor Of Soluble guanylate cyclase (sGC), and NOS blockade by NG methyl-L-arginine (L-NMA; 10 mu M). Cytochalasin D (cytD, 10 mu M) increased RBC surface and mimicked CTX effect but did not prevent the P-CTX-1-induced L-NMA-sensitive extra increase. Calculations revealed that P-CTX-1 and cytD increase RBC total surface envelop and volume. These data strongly suggest that the molecular mechanisms underlying CTXs-induced RBC swelling involve the NO pathway by an activation of the inducible NOS, leading to sGC activation which modulates intracellular cGMP and regulates L-type Ca2+ channels. The resulting increase in intracellular Ca2+ content, in turn, disrupts the actin cytoskeleton, which causes a water influx and triggers a Ca2+-activated K+ current through SK2 isoform channels. (c) 2005 Elsevier Inc. All rights reserved. %$ 020 ; 050