Referenced in: none

Automatically associated channels: Kir2.3

Title: Cation-selective channels in amphibian epithelia: electrophysiological properties and activation.

Authors: W Van Driessche, J Simaels, I Aelvoet, D Erlij

Journal, date & volume: Comp Biochem Physiol A Comp Physiol, 1988 , 90, 693-9

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/2460285

Abstract
1. Na+ as well as Li+ move across the apical membrane through amiloride-sensitive ionic channels. 2. K+ movements across the apical membrane occur through Ba2+- and Cs+-sensitive channels which do not allow the passage of Na+ or Li+. 3. A third pathway in the apical membrane is permeable for Na+, K+, Cs+, Rb+, NH+4 and Ti+. The currents carried by these monovalent cations are blocked by Ca2+ and divalent cations as well as La3+. 4. In the urinary bladder, the Ca2+-sensitive currents are stimulated by oxytocin, activators of cytosolic cAMP and cAMP analogues. Also the oxytocin activated currents are blocked by divalent cations and La3+. 5. Nanomolar concentrations of mucosal Ag+ activate the third channel and open the pathway for movements of Ca2+, Ba2+ and Mg2+, which are known to permeate through Ca2+ channels in excitable tissues.