Page 48 - Color_Atlas_of_Physiology_5th_Ed._-_A._Despopoulos_2003

C. Control of ion channels

1 2
Membrane potential K + Acetylcholine External ligands
(nicotinergic)
GABA
Cl –

Na +
Na +
Cl – Cl –
Ca 2+
Interstice Cytosol Electrical Potentials II
cAMP
Ca 2+
Cl –
Cl – cGMP
IP 3
Ca 2+ Na +
Ca 2+
pH Tyrosine Plate 1.17
kinases
ATP
Cl –
5 K +
Membrane
stretch
K + K +

4 K + Cl – 3 Intracellular
messenger
Intracellular substances
metabolites

! Intracellular metabolites (! C4) such as ATP
+
(e.g., in K channels in the heart and B cells in
+
pancreatic islets) or H+ ions (e.g., in K chan-
nels in renal epithelial cells);
! Membrane stretch (! C5), the direct or in-
direct (?) effects of which play a role in Ca 2+
channels of smooth muscle fibers and gen-
+
–
erally in normal K and Cl channels in swelling
cells.

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Despopoulos, Color Atlas of Physiology © 2003 Thieme
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