The effect of amiloride and benzimidazoleguanidine added to the inside medium on electrolyte pathways in the frog skin glands.
Serosal amiloride inhibits Na+, K+ and Cl- efflux and reduces short-circuit current and transepithelial conductance in noradrenaline-stimulated frog skin in which the sodium channels in the apical membrane are blocked by amiloride. BIG (benzimidazoleguanidine) inhibits Na+ and K+ efflux and reduces the short-circuit current. In some skins BIG decreased and in others it increased Cl- efflux and conductance. The variable response appears to be due not only to inhibition of salt extrusion from the gland cells but also to activation of Cl- transport through the mitochondria-rich cells, since it was shown that BIG could increase Cl- efflux in gland-free preparations. Different target mechanisms in the gland cells where the two substances may exert their effect are discussed.
Eskesen
K
K
Department of General Physiology and Biophysics, University of Copenhagen, Denmark.
Ussing
H H
HH
D000584:Amiloride / Q000494:pharmacology*; D000818:Animals; D002463:Cell Membrane Permeability / Q000187:drug effects; D002713:Chlorine / Q000378:metabolism; D004573:Electrolytes / Q000378:metabolism*; D006146:Guanidines / Q000494:pharmacology*; D009638:Norepinephrine / Q000494:pharmacology; D011188:Potassium / Q000378:metabolism; D011896:Rana temporaria; D012867:Skin / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D015222:Sodium Channels / Q000187:drug effects
D004573:Electrolytes; D006146:Guanidines; D015222:Sodium Channels; D002713:Chlorine; C032996:2-benzimidazolylguanidine; D000584:Amiloride; D012964:Sodium; D011188:Potassium; D009638:Norepinephrine