Faster kinetics of quantal catecholamine release in mouse chromaffin cells stimulated with acetylcholine, compared with other secretagogues

2016 ◽  
Vol 139 (5) ◽  
pp. 722-736 ◽  
Author(s):  
Enrique Calvo-Gallardo ◽  
Ángela López-Gil ◽  
Iago Méndez-López ◽  
Carmen Martínez-Ramírez ◽  
Juan Fernando Padín ◽  
...  
2013 ◽  
Vol 305 (2) ◽  
pp. C160-C172 ◽  
Author(s):  
Juan-Fernando Padín ◽  
José-Carlos Fernández-Morales ◽  
Román Olivares ◽  
Stefan Vestring ◽  
Juan-Alberto Arranz-Tagarro ◽  
...  

The activity of the plasmalemmal Na+/Ca2+ exchanger (NCX) is highly sensitive to temperature. We took advantage of this fact to explore here the effects of the NCX blocker KB-R7943 (KBR) at 22 and 37°C on the kinetics of Ca2+ currents ( ICa), cytosolic Ca2+ ([Ca2+]c) transients, and catecholamine release from bovine chromaffin cells (BCCs) stimulated with high K+, caffeine, or histamine. At 22°C, the effects of KBR on those parameters were meager or nil. However, at 37°C whereby the NCX is moving Ca2+ at a rate fivefold higher than at 22°C, various of the effects of KBR were pronounced, namely: 1) no effects on ICa; 2) reduction of the [Ca2+]c transient amplitude and slowing down of its rate of clearance; 3) blockade of the K+-elicited quantal release of catecholamine; 4) blockade of burst catecholamine release elicited by K+; 5) no effect on catecholamine release elicited by short K+ pulses (1–2 s) and blockade of the responses produced by longer K+ pulses (3–5 s); and 6) potentiation of secretion elicited by histamine or caffeine. Furthermore, the more selective NCX blocker SEA0400 also potentiated the secretory responses to caffeine. The results suggest that at physiological temperature the NCX substantially contributes to shaping the kinetics of [Ca2+]c transients and the exocytotic responses elicited by Ca2+ entry through Ca2+ channels as well as by Ca2+ release from the endoplasmic reticulum.


2007 ◽  
Vol 92 (8) ◽  
pp. 2735-2746 ◽  
Author(s):  
Kim San Tang ◽  
Nan Wang ◽  
Amy Tse ◽  
Frederick W. Tse

2006 ◽  
Vol 99 (2) ◽  
pp. 628-640 ◽  
Author(s):  
R. H. S. Westerink ◽  
M. B. Rook ◽  
J. P. Beekwilder ◽  
W. J. Wadman

Author(s):  
Magda M. Santana ◽  
Joana Rosmaninho-Salgado ◽  
Manuella Kaster ◽  
Vera Cortez ◽  
Rodrigo A. Cunha ◽  
...  

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