Chloride conductance in amphibian skin: Regulatory control in the skin of Rana pipiens

Chloride conductance across the isolated skin of Rana pipiens shows a voltage-activated component (GClV) which requires the presence of mucosal Cl. GClV is normally low or dormant. It is stimulated by elevated intracellular cAMP, irrespective whether originating from application of ß-adrenergic agonists (isoproterenol), stimulators of the adenylyl-cyclase (forskolin), inhibitors of the phosphodiesterases (isobutyl-methyl-xanthine) or membrane-permeable cAMP analogues (CPT-cAMP). Baseline GCl under inactivating conditions increases also with cAMP dose-dependently. The data indicate that cAMP is a central regulator of the passive, conductive chloride transport across amphibian skin.