Role of Thapsigargin-Sensitive Intracellular Ca2+ Pools in Secretion Induced by Muscarinic Agonists in Porcine Adrenal Chromaffin Cells

2006 ◽  
Vol 59 (6) ◽  
pp. 2224-2229 ◽  
Author(s):  
Yanping Xu ◽  
Emilia P. Duarte ◽  
Erik J. Forsberg
Neuron ◽  
1996 ◽  
Vol 16 (1) ◽  
pp. 219-228 ◽  
Author(s):  
James Herrington ◽  
Young Bae Park ◽  
Donner F Babcock ◽  
Bertil Hille

2009 ◽  
Vol 109 (3) ◽  
pp. 911-922 ◽  
Author(s):  
Joana Rosmaninho-Salgado ◽  
Inês M. Araújo ◽  
Ana Rita Álvaro ◽  
Alexandrina F. Mendes ◽  
Lígia Ferreira ◽  
...  

1995 ◽  
Vol 269 (1) ◽  
pp. E43-E52 ◽  
Author(s):  
E. J. Forsberg ◽  
Q. Li ◽  
Y. Xu

A large portion (70%) of the secretory response to muscarinic agonists in porcine adrenal chromaffin cells has previously been shown to be dependent on extracellular Ca2+ (Xu et al., J. Neurochem. 56: 1899-1896, 1991). Results presented here show that muscarinic agonists activate a cation-selective channel which is permeable to divalent cations. The muscarinic agonist, methacholine, was found to activate the uptake of Mn2+, which paralleled the ability of methacholine to activate 45Ca2+ uptake as shown previously. Secretion induced by methacholine was not affected by nifedipine, a compound that inhibits dihydropyridine-sensitive voltage-gated Ca2+ channels. In voltage-clamped cells, methacholine activated whole cell currents, which reversed at approximately -20 mV in standard salt solutions. However, with the standard whole cell configuration, the currents were slow to activate and were often erratic. In contrast, when the perforated-patch (nystatin) technique was used to measure whole cell currents, methacholine rapidly activated sustained inward currents. Ion-substitution experiments indicated that the inward currents were carried by Na+, Ba2+, or Ca2+ but not by Cl-. Single-channel currents activated by methacholine were observed in outside-out vesicles, which were electrically accessed using the perforated-patch technique. These channels reversed at -15 mV, had a slope conductance of 20 pS, and were 14-fold more likely to be open in the presence of methacholine. These channels are probably responsible for the extracellular Ca(2+)-dependent secretory response to muscarinic receptor stimulation in porcine adrenal chromaffin cells.


2010 ◽  
Vol 30 (8) ◽  
pp. 1217-1224 ◽  
Author(s):  
Masumi Inoue ◽  
Keita Harada ◽  
Hidetada Matsuoka ◽  
Akira Warashina

Sign in / Sign up

Export Citation Format

Share Document