PMID: 7543248Jul 1, 1995Paper

Cation channel activated by muscarinic agonists on porcine adrenal chromaffin cells

The American Journal of Physiology
E J ForsbergY Xu

Abstract

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 obs...Continue Reading

References

Aug 1, 1992·The Journal of Physiology·G UcedaA G García
Jan 1, 1992·The Journal of Physiology·F AbadA G García
Aug 1, 1991·Journal of Neurochemistry·M A MoroO K Langley
Aug 1, 1988·The Journal of General Physiology·R Horn, A Marty
Jan 1, 1989·Annual Review of Physiology·B P Bean
Oct 1, 1988·The Biochemical Journal·T J HallamJ E Merritt
Oct 1, 1986·Physiological Reviews·S Ozawa, O Sand
Apr 29, 1987·Biochemical and Biophysical Research Communications·R BorgesA G García
Oct 1, 1966·Proceedings of the Society for Experimental Biology and Medicine·A M Poisner, W W Douglas
Oct 1, 1982·The Journal of Physiology·E M FenwickE Neher
Dec 1, 1993·Pflügers Archiv : European journal of physiology·Z Zhou, E Neher
Mar 1, 1993·The Journal of General Physiology·K Nakazawa, P Hess

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Citations

Nov 19, 2011·Journal of Pharmacological Sciences·Keita HaradaMasumi Inoue
Jun 30, 2012·American Journal of Physiology. Cell Physiology·Masumi InoueAkira Warashina

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