Journal article

Publication year: 2006

Pages: 1084-1092

Journal: Neurogastroenterology and Motility

Volume number: 18

Issue number: 12

ISSN: 1350-1925

eISSN: 1365-2982

DOI Link: https://doi.org/10.1111/j.1365-2982.2006.00840.x

Publisher: Wiley: 12 months

Abstract: 
The effects of carbocyclic thromboxane A(2) (cTXA(2); 10(-6) mol L-1) on membrane potential and cytosolic Ca2+ concentration were measured with the whole-cell patch-clamp or the fura-2 method, respectively, at rat myenteric ganglia. cTXA(2) caused a hyperpolarization of myenteric neurones from -19.3 +/- 2.5 to -29.3 +/- 2.3 mV. In addition, the eicosanoid potentiated the carbachol-induced depolarization from 4.2 +/- 1.0 mV under control conditions to 11.1 +/- 1.1 mV in the presence of the cTXA(2) (n = 9). The hyperpolarization was abolished by internal application of CsCl (140 mmol L-1), a non-selective blocker of K+ channels, or EGTA (11 mmol L(-1)in the pipette solution), a chelator of intracellular Ca2+. A similar inhibition was observed in the presence of charybdotoxin (10(-7) mol L-1). Fura-2 imaging experiments revealed a cTXA(2)-evoked increase in the intracellular Ca2+ concentration as indicated by a rise in the fura-2 ratio signal. This response was mediated by a release of Ca2+ from intracellular stores as sarcoplasmic-endoplasmic reticulum Ca2+-ATPase blockade with cyclopiazonic acid (5 x 10(-5) mol L-1) completely abolished the response to cTXA(2). A similar inhibition was observed after blockade of phospholipase C with U-73122 (10(-5) mol L-1). These results suggest an activation of Ca2+-activated K+ channels by cTXA(2) after stimulation of phospholipase C.

Harvard Citation style: Rehn, M. and Diener, M. (2006) Effect of the stable thromboxane derivative, carbocyclic thromboxane A2, on membrane potential of rat myenteric neurones in culture, Neurogastroenterology and Motility, 18(12), pp. 1084-1092. https://doi.org/10.1111/j.1365-2982.2006.00840.x

APA Citation style: Rehn, M., & Diener, M. (2006). Effect of the stable thromboxane derivative, carbocyclic thromboxane A2, on membrane potential of rat myenteric neurones in culture. Neurogastroenterology and Motility. 18(12), 1084-1092. https://doi.org/10.1111/j.1365-2982.2006.00840.x